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Archaeological Surveys of the old city of Xanadu,believed to have 13 Sep 2019, 05:32
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Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the city. The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC.It is thus proven that the Xanadus first developed the urban sewage system,

which of the following is an assumption on which the argument depends ?

A) The Harappans were incapable of building such a sewage system
B) Harappas sewage system was an improved version of that of Xanadu
C) The city that was abandoned first was also built first
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another
E) Harappa's houses were similar to Xanadu's
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C
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Archaeological Surveys of the old city of Xanadu,believed to have 15 Sep 2019, 22:32
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Can you please explain why option C is correct.
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Archaeological Surveys of the old city of Xanadu,believed to have 16 Sep 2019, 00:51
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I’m sorry but C does not prove anything. This is like comparing Egyptian pyramids to Mayan pyramids and saying one gave rise to the other when we know this is not true. What is the source of this question.

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Archaeological Surveys of the old city of Xanadu,believed to have 16 Sep 2019, 02:19
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I think the logic is there, but the argument has been built poorly. There is no indication in the argument whether Xanadu was abandoned first or not. It merely says it existed before BC 2500.
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Archaeological Surveys of the old city of Xanadu,believed to have 16 Sep 2019, 02:54
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Existed before 2500BC, is a way of saying that by 2500BC it was no longer present.

C is pretty straight forward.

Also, all other choices makes no sense.

A) The Harappans were incapable of building such a sewage system....Already mentioned in the passage that the sewage systems were similar, hence they were definitely capable of making it.
B) Harappas sewage system was an improved version of that of Xanadu....Can be a choice, but we do not know the level of improvement in the system. If it was highly improved, then the similarity in them, will be less, and vice versa. It is partially correct. Not completely.
C) The city that was abandoned first was also built first...Correct coice
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another....Out of scope. It basically weakens the argument.
E) Harappa's houses were similar to Xanadu's.....We are talking about similarity in sewage system and not houses.
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Archaeological Surveys of the old city of Xanadu,believed to have 16 Sep 2019, 05:49
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LoneSurvivor
Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the city. The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC.It is thus proven that the Xanadus first developed the urban sewage system,

which of the following is an assumption on which the argument depends ?

A) The Harappans were incapable of building such a sewage system
B) Harappas sewage system was an improved version of that of Xanadu
C) The city that was abandoned first was also built first
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another
E) Harappa's houses were similar to Xanadu's
Show more

premise; Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the cit
IC; The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC
conclusion; It is thus proven that the Xanadus first developed the urban sewage system,

use negation test with options the one which weakens conclusion is correct
A) The Harappans were capable of building such a sewage system ; irrelevant
B) Harappas sewage system was not an improved version of that of Xanadu ; irrelevant
C) The city that was not abandoned first was also built first ; seems to be correct and on the lines of premise
D) There wastransportation between the two cities ,making it impossible for people from one city to visit another; irrelevant
E) Harappa's houses were not similar to Xanadu's irrelevant


option C ; The city that was not abandoned first was also built first ; by this we can say that Harrappa was built earlier than Xandu so therefore Harrapans were first to built sewage system
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Archaeological Surveys of the old city of Xanadu,believed to have 12 Jan 2022, 22:16
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Archit3110
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Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the city. The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC.It is thus proven that the Xanadus first developed the urban sewage system,

which of the following is an assumption on which the argument depends ?

A) The Harappans were incapable of building such a sewage system
B) Harappas sewage system was an improved version of that of Xanadu
C) The city that was abandoned first was also built first
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another
E) Harappa's houses were similar to Xanadu's

premise; Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the cit
IC; The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC
conclusion; It is thus proven that the Xanadus first developed the urban sewage system,

use negation test with options the one which weakens conclusion is correct
A) The Harappans were capable of building such a sewage system ; irrelevant
B) Harappas sewage system was not an improved version of that of Xanadu ; irrelevant
C) The city that was not abandoned first was also built first ; seems to be correct and on the lines of premise
D) There wastransportation between the two cities ,making it impossible for people from one city to visit another; irrelevant
E) Harappa's houses were not similar to Xanadu's irrelevant


option C ; The city that was not abandoned first was also built first ; by this we can say that Harrappa was built earlier than Xandu so therefore Harrapans were first to built sewage system
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I negated C as follows: C) The city that was abandoned first was NOT built first.

Which gives me that Harrapas was abandoned first but it was not built first. Also I dont have anymore info about when Xanadu was abandoned relative to Harrapas. I did a POE and C seemed relevant. Did not try any logic behind it. Any advice?
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Archaeological Surveys of the old city of Xanadu,believed to have 12 Jan 2022, 22:59
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LoneSurvivor
Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the city. The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC.It is thus proven that the Xanadus first developed the urban sewage system,

which of the following is an assumption on which the argument depends ?

A) The Harappans were incapable of building such a sewage system
B) Harappas sewage system was an improved version of that of Xanadu
C) The city that was abandoned first was also built first
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another
E) Harappa's houses were similar to Xanadu's
Show more

Xanadu existed before 2500 BC (so by 2500 BC, it had been abandoned). They had the sewage system.
Harappa was abandoned around 1800 BC. They had a similar sewage system.

Conclusion: Xanadus developed the sewage system first.

There is big jump here, right? We are given that Xanadu was abandoned in 2500 BC while Harappa was abandoned in 1800 BC. So we are concluding that Xanadu developed the system first. To say this, we are assuming that Xanadu was established first and it developed the sewage system first.

What if Xanadu developed in 3000 BC and was abandoned in 2500 BC but Harappa developed in 4000 BC and was abandoned in 1800 BC? Then Harappa would have been the first one to develop the sewage system. Nothing says that the age of the two civilisations need to be the same. Xanadu could have survived for only 500 years while Harappa could have survived for 2200 years.
The point is that information on when the civilisations were abandoned is not enough to tell us when they started and when they set up the sewage systems.

(C) says that the assumption is that the city that was abandoned first was also built first. So, essentially, they have similar ages. This is an assumption we are making to arrive at our conclusion. We are assuming that since Xanadu was abandoned first, it must have been built before Harappa.

Hence, (C) is correct.

All other options are irrelevant.
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Archaeological Surveys of the old city of Xanadu,believed to have 17 Apr 2022, 11:22
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KarishmaB
LoneSurvivor
Archaeological Surveys of the old city of Xanadu,believed to have existed before 2500 BC,prove that a sophisticated sewage system was in place in the city. The system is architecturally very close to one found in Harappa,an ancient Indus Valley civilization city,proven to have been abandoned around 1800 BC.It is thus proven that the Xanadus first developed the urban sewage system,

which of the following is an assumption on which the argument depends ?

A) The Harappans were incapable of building such a sewage system
B) Harappas sewage system was an improved version of that of Xanadu
C) The city that was abandoned first was also built first
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another
E) Harappa's houses were similar to Xanadu's

Xanadu existed before 2500 BC (so by 2500 BC, it had been abandoned). They had the sewage system.
Harappa was abandoned around 1800 BC. They had a similar sewage system.

Conclusion: Xanadus developed the sewage system first.

There is big jump here, right? We are given that Xanadu was abandoned in 2500 BC while Harappa was abandoned in 1800 BC. So we are concluding that Xanadu developed the system first. To say this, we are assuming that Xanadu was established first and it developed the sewage system first.

What if Xanadu developed in 3000 BC and was abandoned in 2500 BC but Harappa developed in 4000 BC and was abandoned in 1800 BC? Then Harappa would have been the first one to develop the sewage system. Nothing says that the age of the two civilisations need to be the same. Xanadu could have survived for only 500 years while Harappa could have survived for 2200 years.
The point is that information on when the civilisations were abandoned is not enough to tell us when they started and when they set up the sewage systems.

(C) says that the assumption is that the city that was abandoned first was also built first. So, essentially, they have similar ages. This is an assumption we are making to arrive at our conclusion. We are assuming that since Xanadu was abandoned first, it must have been built before Harappa.

Hence, (C) is correct.

All other options are irrelevant.
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Hey Karishma, hope you’re doing well. First of all, thank you so much for providing such great explanations on the forum.

I have a small doubt here. So when we take the literal meaning, is choice C somewhat poorly constructed? (or language could have been better?) Because we don’t know whether Xanadu was abandoned. Or do we?

We only know that Harappa was abandoned.

I actually marked C but later ruled it out because of I was not sure of the language used. Am I missing something here?
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Archaeological Surveys of the old city of Xanadu,believed to have 19 Sep 2025, 07:22
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A) The Harappans were incapable of building such a sewage system -> But this one doesn't state the timeline.
B) Harappas sewage system was an improved version of that of Xanadu -> Could be, but doesn't state the timeline.
C) The city that was abandoned first was also built first -> Correct. This one defines the timeline of each city.
D) There was no transportation between the two cities ,making it impossible for people from one city to visit another. -> Each city can develop their own sewage system.
E) Harappa's houses were similar to Xanadu's -> Irrelevant
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Archaeological Surveys of the old city of Xanadu,believed to have 25 Oct 2025, 02:54
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I attempted in a mock and marked option D - thinking Xanadu was never abandoned - atleast that was never written so. So it could be that - this civilisation existied even when Harappa was there - then in that kind of scenario it there was travel - it could be a possibility that this was built in Harapa first and then due to people's movement it got built in Xanadu. And option C abandonment was never at the heart of argument - what is wrong with my thinking?
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Archaeological Surveys of the old city of Xanadu,believed to have 09 Nov 2025, 10:55
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Even i marked D , thinking same . Can someone explain why D is not the right choice here ?

Dream009
I attempted in a mock and marked option D - thinking Xanadu was never abandoned - atleast that was never written so. So it could be that - this civilisation existied even when Harappa was there - then in that kind of scenario it there was travel - it could be a possibility that this was built in Harapa first and then due to people's movement it got built in Xanadu. And option C abandonment was never at the heart of argument - what is wrong with my thinking?
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Archaeological Surveys of the old city of Xanadu,believed to have 09 Nov 2025, 21:20
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What The Argument Compares
Xanadu: Existed before 2500 BC (when it was BUILT)
Harappa: Abandoned around 1800 BC (when it ENDED)
Conclusion: Xanadu developed the sewage system first

The Problem
The argument compares two different types of dates - a founding date (Xanadu) and an abandonment date (Harappa).
Can you compare these?
Simple analogy: Restaurant A opened in 1950. Restaurant B closed in 1980. Which opened first? You can't tell! Restaurant B could have opened in 1920 (before A) or 1970 (after A).

Why C Is The Assumption
To conclude Xanadu was first, the argument must assume: "The city abandoned first was also built first" (Option C)
If C is false, Harappa could've been built in 3000 BC and abandoned 1800 BC. This makes Harappa OLDER than Xanadu. Conclusion destroyed.

Why Not D?
Even with no travel between cities, the argument still fails because we're comparing a founding date vs. abandonment date. That comparison is meaningless without assuming C.
The argument breaks at the dating logic stage (C), not the cultural exchange stage (D).

Bottom Line
The 1800 BC abandonment date is the ONLY timeline information about Harappa. The author uses it to prove Xanadu was older. This only works if abandoned first = built first. That's Option C.

RM4321
Even i marked D , thinking same . Can someone explain why D is not the right choice here ?


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