Rainforests produce a large percentage of the Earth s supply

Question

Rainforests produce a large percentage of the Earth’s supply of oxygen. Continued destruction of these rainforests is likely to reduce the Earth’s oxygen supply to levels that will threaten the existence of all oxygen-dependent life on Earth.

Which of the following, if true, most seriously weakens the prediction above?

(A) All of the oxygen produced by the Earth’s rainforests is consumed by bacteria and animals living in those forests
(B) Some of the oxygen produced by the Earth’s rainforests escapes through the upper atmosphere without being consumed
(C) The oxygen produced by rainforests is consumed by animals all over the Earth
(D) The Earth’s rainforests are being destroyed at a rate of hundreds of acres every day
(E) Rainforests contain the most diverse selection of oxygen-dependent animals

soumanag · Answer

conclusion: Continued destruction of rain forests will reduce the Earth’s oxygen supply to levels that will threaten the existence of  all  oxygen-dependent life on Earth.
premise:Rainforests produce a large percentage of the Earth’s supply of oxygen
Ideal answer: In spite of continued destruction of rain forests existence of all oxygen-dependent life on Earth will not be threatened.

Correct option A. All the oxygen produced is consumed by animals living in these rain forests => animals leaving elsewhere have some alternate source of oxygen.

ankitranjan · Answer

Got it right.Some what straight.

aj33 · Answer

There is an assumption here. that all the oxygen is not used by anything in the rainforest. i.e the oxygen is not worthless. it reaches the other parts of earth.
and A is the answer

Abhishek009 · Answer

(A) If the oxygen produced by the Earth’s rainforests is  " consumed by the bacteria and animals living in those rainforest "  then it will not affect  " the existence of all oxygen-dependent life on Earth. " .

Hence option (A) is weakening the conclusion..

(B) Out of scope.

(C) Strengthens the Conclusion.

(D) Simply states the severity of destruction of rainforests ; doesn't weaken the conclusion.

(E) Irrelevant to the discussion

Hence IMHO (A)

rhine29388 · Answer

option A is the clear weakener - if oxygen produced by rainforests is consumed by bacteria and animals living in those forests then it is probably not whole of the earth's oxygen-dependent lives problem
option B is partially true and somewhat out of scope because it provides alternate reasoning but takes the reasoning off topic by mentioning upper atmosphere
option C is a clear strengthener 
option D states a fact or a missing premise but doesn't help in weakening so eliminate 
option E is also out of scope option as it provides irrelevant information

VerbalBot · Answer

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Rainforests produce a large percentage of the Earth s supply

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Rainforests produce a large percentage of the Earth s supply

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