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Two centuries ago, Tufe Peninsula became separated from the mainland, isolating on the newly formed Tufe Island a population of Turfil sunflowers. This population’s descendants grow to be, on average, 40 centimeters shorter than Turfil sunflowers found on the mainland. Tufe Island is significantly drier than Tufe Peninsula was. So the current average height of Tufe’s Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe’s environmental conditions.

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


Option A:

There are no types of vegetation on Tufe Island that are known to benefit from dry conditions.

Option B:

There were about as many Turfil sunflowers on Tufe Peninsula two centuries ago as there are on Tufe Island today.

Option C:

The mainland’s environment has not changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.

Option D:

The soil on Tufe Island, unlike that on the mainland, lacks important nutrients that help Turfil sunflowers survive and grow tall in a dry environment.

Option E:

The 40-centimeter height difference between the Turfil sunflowers on Tufe Island and those on the mainland is the only difference between the two populations.

Difficulty Level



Option C is the right answer

Option Analysis

Question type: Find the Assumption

Summary of the argument: The island got separated from the mainland. The climatic conditions at both of these places are different from each other. Hence the author attributes one to the other and says the change in climatic conditions are the reason for the difference in the sunflower growth.

A) We are not worried about other types of vegetation.

B) Again the number of sunflowers does not account to the logic of the argument.

C) Correct Answer

D) This weakens the argument by giving another cause to why the sunflowers are growing differently.

E) This doesn’t tell us why the change is present.