While global temperatures have risen sharply over the last century, th

Question

While global temperatures have risen sharply over the last century,  they have only recently eclipsed the Medieval period, during which scientists theorize that a  series of volcanic eruptions sent the earth into a period of historic warmth.

A. they have only recently eclipsed the Medieval period, during which scientists theorize that a
B. they have only recently eclipsed those of the Medieval period, during which scientists theorize that a
C. it has only recently eclipsed the Medieval period, during which, scientists theorize, a
D. it has only recently eclipsed that of the Medieval period, during which scientists theorize a
E. they have only recently eclipsed those of the Medieval period, during which, scientists theorize, a

max0010 · Accepted Answer

the main subject here is "temperatures", so we need a pronoun that refers to "temperatures" and most importantly agrees with the subject's number, so "they" in A, B and E correctly refers back to the main subject. Note: in option C and D the pronoun "it" logically refers to the noun "century", but then these options do not convey the right meaning (how can a century eclipse a period in time?), so options C and D are out.

Now let's look at options A, B and E
A -> "they" (temperatures) have only recently eclipsed the Medieval period. How can temperatures eclipse a period in time, doesn't make sense, technically a possessive pronoun is missing, so option A is out.
B -> we have the required possessive pronoun "those" but we see a meaning issue in this option, the part " during which scientists theorize " tells us that it was the Medieval period when the scientists theorized the explanation of the volcanic activity, this meaning is wrong, so option B is out
E-> the punctuation helps out in this option, this option correctly conveys the meaning that  recently  the scientists came up with a theory that during the medieval period the temperatures rose due to intense volcanic activity.

E wins!

BillyZ · Answer

OFFICIAL SOLUTION

Difficulty Level: 750-800

This problem provides two very clear decision points for you to get started:

1) "they" vs. "it" as the first word of the sentence

2) "that of" vs. "those of" vs. (no possessive) in relation to "the Medieval period"

The key to both of these is recognizing the subject of the sentence which is "global temperatures." Since temperatures is plural, the pronoun that corresponds to them must be "they" and you can eliminate choices C and D.

Then notice that the comparison is between current global temperatures and the temperatures during the Medieval period; you cannot logically compare "temperatures" with the timeframe, so you need to have "those of" (which B and D have but A does not) to properly draw the comparison.

Between A and E, notice that the only difference is commas around "during which." Why is that important? Here you're dealing with a tense/timeline decision. Since "theorize" is present-tense but the Medieval period is clearly in the past (even if you're not a historian, the fixed past tense "sent" outside the underline tells you that those volcanoes were in the past), you cannot have "scientists theorize" as part of the phrase "during which." The scientists currently theorize that volcanoes caused the global warming, so you need to separate that subject-verb from the modifier "during (the Medieval period)." This means that answer choice E is correct.

hotshot02 · Answer

I was confused between B and E. Ultimately, I chose E but i am still not sure.

sureshpanda20 · Answer

C..they can be used for living beings..it is for inanimate

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gvvsnraju@1 · Answer

I completely fail to understand the intended meaning of " they have only recently eclipsed the Medieval period"
Kindly help!!!
Thanks in advance

abhishekdadarwal2009 · Answer

While global temperatures have risen sharply over the last century, they have only recently eclipsed the Medieval period, during which scientists theorize that a series of volcanic eruptions sent the earth into a period of historic warmth.

A. they have only recently eclipsed the Medieval period, during which scientists theorize that a The scientist did not theorized during the medival period but they theorised about medival period tempratures.
 B. they have only recently eclipsed those of the Medieval period, during which scientists theorize that a The sentence means that the scientist theorized during the medival period and not about the medival period.
 C. it has only recently eclipsed the Medieval period, during which, scientists theorize, a The non underlined sentence refer to the tempratures as plural so 'it' cannot be used.
 D. it has only recently eclipsed that of the Medieval period, during which scientists theorize a  The non underlined sentence refer to the tempratures as plural so 'it' cannot be used.
 E. they have only recently eclipsed those of the Medieval period, during which, scientists theorize, a Correct meaning

guialain · Answer

Lot of commas in answer D
but i admit. D is the best option.
Wrongly selected B, but the meaning is distorted with that option

sayantanc2k · Answer

".. they have only recently eclipsed the Medieval period" does not make any sense - The correct option is:
"...they have only recently eclipsed those of the Medieval period".

Here "they" has been used to replace "global temperatures" and "those" has been used to replace temperatures.

This part is thus as follows:
"...global temperatures have only recently eclipsed temperatures of the Medieval period".

"Eclipsed" means "obscured". The complete sentence thus means:
Global temperatures have risen sharply over the last century - but they were never above the temperatures in the Mediaval period. Only recently global temperatures rose above (i.e. eclipsed) the temperatures of the Mediaval period.

sayantanc2k · Answer

No, Option D is wrong. The pronoun "it" does not have a singuar antecedent.

Nunuboy1994 · Answer

this correctly uses commas to illustrate that scientists developed a theory in the Medieval period in the present

bkpolymers1617 · Answer

This question is wrong.  "While"   has a very specific use on the GMAT- It can not be used for comparisons. In this problem, it is being used for comparison. Plus, I believe that there should be a "that" at the end of the sentence after theorize. Thanks

VodkaHelps · Answer

I answered this question correctly. However, I still wonder what role does "scientists theorize" play in the sentence. Is it a modifier? If so I cannot definitely say what it modifies. What I can clearly see is the phrase "scientists theorize" gives us the information about who was the author of the claim that during the Medieval period a series of volcanos...

Please advise.

aragonn · Answer

alexlearning17

B. they have only recently eclipsed those of the Medieval period, during which scientists theorize that a ---- this choice is saying that in medieval period scientists theorize something. sending a wrong meaning indeed.
E. they have only recently eclipsed those of the Medieval period, during which, scientists theorize, a ---- here this become a modifier saying what scientists theorize and then a theory is given. indeed very subtle.

Hope it helped.

VodkaHelps · Answer

Thank you for a reply. I understand that it is a modifier, but I can't figure out what type of modifier is that. Is it adverbial modifier, which modifies the whole action after it?

Rollroll · Answer

THEY HAVE IS CORRECTLY MODIFYING SCIENTISTS , MEDIEVAL PERIOD IS FOLLOWED BY DURING WHICH IN COMMAS SUCH THAT THEY CAN REFER CLEARLY TO SCIENTISTS..ANS E

SeaGul · Answer

Who is "THEY"? - global temperatures? I am still not comfortable with using "THEY" for inanimate subjects in English

.. Do we have pronouns referred only for alive objects and only for inanimate subjects? Is anybody have some good full grammar source about it? Thanks in advance!

sameeruce08 · Answer

please correct me

i think household is adjective modifying noun incomes

so how can 49% of incomes be less than poverty line

Ss6479118 · Answer

A and C compare the temperatures to the Medieval Period, not its temperatures. This is an incorrect comparison. D is wrong because it uses the singular ‘it’ to refer to the ‘plural’ temperatures. B has a meaning issue, B tells us that the scientists theorized during the medieval period.
 
E is the correct answer.

arorni · Answer

I still can't understand why E is correct especially with lot of commas. Can someone please explain it?

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While global temperatures have risen sharply over the last century, th

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While global temperatures have risen sharply over the last century, th

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