GMAT Critical Reasoning (CR) | Re: By examining fossilized beetles a research team has produced t

E it must be, Suppose A's maximum temperature tolerance in last 22000 years is estimated to be 96 Celsius. But if temperature tolerance of A initially were 150 Celsius and then changes to 96...then researches wont be able to find out most extreme temperature of that place.
So writer assumes that the change in temperature tolerance didn't change significantly. it might ranges from 105 to 95 and that is normal.

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