LSAT Explanation PT 38, S1, Q4: An anthropologist hypothesized that a certain

LSAT Question Stem

Which one of the following, if true, most strengthens the anthropologist's counterargument? 

Logical Reasoning Question Type

This is a Strengthen question. 

Correct Answer

The correct answer to this question is C. 

LSAT Question Complete Explanation

Let's first break down and analyze the argument in the passage. The anthropologist hypothesized that a medicinal powder contained a significant amount of the deadly toxin T. She tested the powder, but the test came back negative. However, the anthropologist claims that the test results are invalid because the powder was accidentally tested in an acidic solution. The chemist accuses her of fraud. The conclusion of the argument is that the anthropologist's test results are invalid due to the acidic solution.

To help you better understand this situation, let's use a simple example. Imagine you're trying to find out if a glass of water contains a certain type of bacteria. You accidentally test the water in a solution that is known to kill the bacteria. The test comes back negative, but you argue that the results are invalid because the bacteria-killing solution may have affected the outcome.

Now, let's create an "Evaluate" question for this argument: "Does the acidic solution affect the detection of toxin T in the medicinal powder?"

The question type for this problem is Strengthen, and we need to find an answer choice that strengthens the anthropologist's counterargument.

a) While this answer choice provides some background on why the anthropologist decided to test the powder, it doesn't directly strengthen the claim that the test results were invalid due to the acidic solution.

b) This answer choice introduces a conditional statement about the activity level of toxin T declining if the powder is stored for a long time. However, we don't know if the powder was stored for a long time, and it doesn't address the issue of the acidic solution affecting the test results.

c) This answer choice directly strengthens the anthropologist's counterargument. It states that when toxin T is put into an acidic solution, it becomes undetectable. This means that the acidic solution could have affected the test results, making them invalid, as the anthropologist claims.

d) The availability of a fresh batch of powder for a repeat analysis doesn't strengthen the anthropologist's counterargument about the initial test results being invalid due to the acidic solution. It is irrelevant to the main issue at hand.

e) This answer choice mentions that the type of analysis used was insensitive to very small amounts of toxin T. However, the anthropologist was looking for a significant amount of toxin T, not small amounts. Additionally, this answer choice doesn't address the issue of the acidic solution affecting the test results.

Therefore, the correct answer is C, as it strengthens the anthropologist's counterargument by showing that the acidic solution could have affected the detection of toxin T in the medicinal powder.