Cotton grass, which grows only in arctic regions, has been the only su

Question

Cotton grass, which grows only in arctic regions, has been the only summertime source of protein available to caribou. Caribou that do not get adequate amounts of protein in the summer are unable to reproduce the following year. Rising average temperatures in arctic regions, however, are causing cotton grass to disappear. Therefore, if the warming trend continues, caribou are likely to become extinct.

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

A. cotton grass is the only one of the caribou’s food sources that is becoming scarce as temperatures rise in arctic regions.
B. caribou that do not eat enough protein to reproduce do not live as long as caribou that do
C. The warming trend in arctic regions will not enable other plants capable of providing protein to caribou to grow there.
D. The caribou is the only animal that depends on cotton grass as a major source of food.
E. If the warming trend continues and cotton grass disappears from arctic regions, then cotton grass will be extinct.

genericUser · Answer

Cotton grass, which grows only in arctic regions, has been the only summertime source of protein available to caribou. Caribou that do not get adequate amounts of protein in the summer are unable to reproduce the following year. Rising average temperatures in arctic regions, however, are causing cotton grass to disappear. Therefore, if the warming trend continues, caribou are likely to become extinct.

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

rising temp -> less cotton grass (only protein source caribu need to reproduce) ->  ???  -> caribou likely to become extint

need  ???  that create a good logica link

A. cotton grass is the only one of the caribou’s food sources that is becoming scarce as temperatures rise in arctic regions.
No. Caribou may feed on other plants, but they need the protein
B. caribou that do not eat enough protein to reproduce do not live as long as caribou that do
No. This strengthen the conclusion, but it is not a required assumption
 C.  The warming trend in arctic regions will not enable other plants capable of providing protein to caribou to grow there.
Correct. What if higher temperature will allow other protein source to grow? If other protein source are not availbale caribou will not be able to reproduce
D. The caribou is the only animal that depends on cotton grass as a major source of food.
No. Not the point at issue
E. If the warming trend continues and cotton grass disappears from arctic regions, then cotton grass will be extinct.
No. Not interested in that

Feedback appreciated.

CYp113 · Answer

I want to go with C. (But not 100% sure)
Negate C:
If The warming trend in arctic regions WILL enable other plants capable of providing protein to caribou to grow there. Then, caribou are NOT likely to become extinct.

dev21212121 · Answer

Hi  KarishmaB  please tell me why it is not E, i believe it's too vague.

miag · Answer

Hi,

I believe E) mixes up caribou being extinct with cotton grass being extinct (which is not really necessary)..do we need cottongrass to be extinct for caribou to be extinct? not really
In order for caribou to be extinct, it is sufficient for cotton grass to disappear from arctic regions where the caribou live. It could still exist in other places but that wouldn't help the caribou.

Whenever dealing with an assumption question, always ask yourself do I need this to be true for conclusion to hold true? Is it a must have condition?

Hope this helps!

KarishmaB · Answer

First note that option (E) is given to us. ( Cotton grass, which grows only in arctic regions ... so if arctic regions become warmer and cotton grass disappears, it is likely to become extinct)

Next, we don't really care whether summer grass becomes extinct or is left in very low concentration such that caribou do not get their sufficient protein intake and are not able to reproduce. We don't need to assume anything about the extinction of summer grass for our conclusion hence ignore (E).

Cotton grass, which grows only in arctic regions, has been the only su

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Cotton grass, which grows only in arctic regions, has been the only su

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