I think A. Conclusion states that the destruction of tropical forests will threaten ALL (keyword) oxygen dependent life. Answer A says that only those oxyden dependent organisms IN the tropical forests consume ALL of the oxygen...meaning that theres none left for those oxygen dependent organisms outside of the tropical forests or basically, all of the remaining oxygen dependent species.

A--yes
B--the conclusion focuses on the effect of reduced oxygen on oxygen dependent life. this answer choice doesn't and can trap those who assume too much. take it at surface value. so what if some oxygen escapes? none of that oxygen is consumable anyway so we're still stuck with the same "scarce" supply.
C--just because its consumed by all animals doesn't necessarily mean that its reduction will threaten all those animals (can't reverse it). all those animals could also consume oxygen of other forests.
D--doesn't tell us anything about the oxygen issue (could strengthen stimulus)
E--irrelevant

IMO A

IMO:A

IF "all of the oxygen produced by the earth's tropical forests is consumed by bacteria and animals living in those forests. " then even if the forests are destroyed it wont threaten the existence of all oxygen-dependent life on earth. ..affect just the animals living in the forest.


thanks.

IMO A

A, Weaken,
B, Irrelevance
C, strengthen,
D, Irrelevance
E, out of scope

OA: A :roll:

I'd say A but I'm afraid more because of my intuition than any logic.