Because there are no habitable planets other than Earth in

Yeah Anish,

The difference was of Most and All

Thanks,

Narenn

If the conclusion states that human beings do not need to live on planets, then answer C makes the most sense because it mentions that ALL of human beings are physiologically unable to develop and function properly outside the confines of a strong gravity field.
The correct answer should explain why Humans CANNOT leave planets. This answer C would weaken to conclusion. I think A would weaken as well but not as much as C. I missed the wording so I picked A at first but I think C is correct. What is the official right answer?

Let's stick to the highlighted conclusion.
A) Most human beings are physically unable to withstand acceleration out of gravity wells.
Is acceleration the issue here?
B) Minute amounts of trace elements available only on Earth are required for human subsistence.
Can the elements not be provided outside the Earth?
C) Human beings are physiologically unable to develop and function properly outside the confines of a strong gravity field.
The gravity fields exist only on planets and human beings need gravity fields to live.
D) Given current technology, it would take more than eight years to complete a round trip from Earth to the asteroid belt and back.
Irrelevant.
E)The resources of asteroids are more likely to be exploited by the descendants of colonists from Earth.
Out of scope.

i easily reached the answer by POE.
1. strengthens the argument
2. looks like a strengthener so no.
3. aha, people can't live without gravity so definitely a weakener.
4. how long it will take is out of scope.
5. who will exploit the resources is out of scope.

C it is.

Because there are no habitable planets other than Earth in our solar system and because it is unlikely we will ever have the capability to reach other systems, the conclusion that humankind will never colonize outer space seems justified. Consider, however, that every planet lies at the bottom of a deep gravity well. It not only takes energy to lift people and material out of such wells; it also takes considerable energy to lower them to the bottom in good working condition. Human beings need air, water, and food, but we need not continue to supply ourselves with these necessities under such inefficient conditions. The asteroid belt between Mars and Jupiter contains billions of tons of the ices of water, ammonia, and carbon dioxide, everything needed to provide food, air, and water, as well as abundant metals from which to build shelter. And relatively little energy would be required to exploit those vast resources because the asteroids, having little mass individually, do not lie at the bottoms of deep gravity wells. Therefore, human beings do not need to live on planets.

NO habitable planet + Incapability to reach other planet => human will not colonized outer space
it also takes considerable energy to lower them to the bottom in good working condition.
Therefore, human beings do not need to live on planets. Human can live on The asteroid belt.

Pre-thinking :-
1. Ok, water is available there. But what about capability to reach those asteroids.
2. What if there is some other conditions that are prohibiting us to live in asteroid.

Which of the following statements, if true, would most weaken the conclusion drawn in the passage above?

A) Most human beings are physically unable to withstand acceleration out of gravity wells.

B) Minute amounts of trace elements available only on Earth are required for human subsistence.
C) Human beings are physiologically unable to develop and function properly outside the confines of a strong gravity field.

I find A,B,E very close.
A => if Most human beings are physically unable to withstand acceleration out of gravity wells, then how will they reach to Asteriods. They need a mechanism. From the premises we don't know about this availability.

B=> if Minute amounts of trace elements are available only on Earth are required for human subsistence and not at asteriods, then our conclusion stands invalid. We only know about "abundant metals from which to build shelter" we don't know about trace elements.

C is of course correct.

Hi Experts ,
B sates that minute amounts of trace elements that are available only on earth are required fro human subsistence .
Does it not weaken the conclusion ?
If those elements are found only on the earth then it would not be possible to leave earth and live elsewhere.

Please explain what is wrong with my reasoning .

MartyMurray

Why cant B be a weakener. Doesn't B give a strong reason to live on planet?

First of all, this question is pretty weak, as the passage never really makes clear that the idea that it is discussing is human's inhabiting asteroids.

Regarding your specific question, B is not a clear weakener, because conceivably the substances found only on Earth could be transported to the asteroids.

Contrast B with C, which makes clear that living on asteroids is essentially out of the question.

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