LSAT Question Stem

The answer to which one of the following questions would contribute most to an evaluation of the argument? 

Logical Reasoning Question Type

This is an Evaluate question. 

Correct Answer

The correct answer to this question is A. 

LSAT Question Complete Explanation

The argument in the passage is structured as follows: The authors of an article claim that there is no evidence to support the idea that the rate of extinction of animal species is accelerating. The passage disagrees with the authors and provides data on North American fish species and subspecies that have vanished in the twentieth century to support the idea that the rate of extinction is indeed accelerating. The premise of the argument is the data on fish species, and the conclusion is that the authors of the article are wrong.

To make this more relatable, consider an example where a group of people claim that there is no evidence to support the idea that the average temperature on Earth is increasing. Someone disagrees and provides data on the increasing temperatures in a specific region to support the idea that the average temperature is indeed increasing.

The "Evaluate" question for this argument would be: "Is the data on fish species representative of animal species in general with regard to their rate of extinction?"

The question type of this problem is Evaluate, and it asks us to identify which answer choice would contribute most to an evaluation of the argument.

Answer choice A asks if the fish species and subspecies that became extinct are unrepresentative of animal species in general with regard to their pattern of extinction. This is the correct answer because if the fish species are not representative, the argument's conclusion is weakened, and if they are representative, the conclusion is strengthened. This directly addresses the logical gap between the premise and the conclusion of the argument.

Answer choice B asks about the populations of the extinct fish species and subspecies in 1950. This choice does not address the logical gap between the premise and the conclusion, as it only focuses on the fish species and not on the broader animal species.

Answer choice C asks if any of the extinct fish species or subspecies originated from outside North America. This choice is irrelevant to the argument, as the geographical origin of the species does not affect the rate of extinction and its relation to other animal species.

Answer choice D asks about the proportion of endangered North American fish species and subspecies in 1950 that are now thriving. This choice does not address the logical gap between the premise and the conclusion, as it only focuses on the fish species and not on the broader animal species.

Answer choice E asks if any of the extinct fish species or subspecies were commercially important. This choice is irrelevant to the argument, as the commercial importance of the species does not affect the rate of extinction and its relation to other animal species.

In conclusion, answer choice A is the correct answer because it directly addresses the logical gap between the premise and the conclusion of the argument, helping to evaluate the argument's validity.