LSAT Explanation PT 37, S4, Q2: The vomeronasal organ (VNO) is found

LSAT Question Stem

Which one of the following, if true, most weakens the argument? 

Logical Reasoning Question Type

This is a Weaken question. 

Correct Answer

The correct answer to this question is A. 

LSAT Question Complete Explanation

The question type for this problem is Weaken, which means we are looking for an answer choice that undermines the conclusion or the relationship between the premises and the conclusion.

Let's first summarize and analyze the argument in the passage. The passage discusses the vomeronasal organ (VNO), which is found in the noses of various animals. In humans, the VNO is detectable, but only microscopically. When researchers stimulate VNO cells in humans, the subjects report subtle smell sensations. The conclusion of the argument is that the VNO, though not completely understood, is a functioning sensory organ in most humans.

The argument's structure can be broken down as follows:

1. Premise: Most humans have a VNO that is detectable, though only microscopically.

2. Premise: When researchers stimulate VNO cells in humans, subjects report subtle smell sensations.

3. Conclusion: The VNO is a functioning sensory organ in most humans.

An "Evaluate" question for this argument could be: "Are the subtle smell sensations experienced by the subjects solely caused by the stimulation of VNO cells?"

Now let's discuss each answer choice:

a) This answer choice weakens the argument by suggesting that researchers might have stimulated other cells in addition to VNO cells, which could have caused the subtle smell sensations. If this is true, it would undermine the conclusion that the VNO is a functioning sensory organ in most humans. This is the correct answer choice.

b) This answer choice doesn't weaken the argument, as it only provides information about the relative development of the human VNO compared to other animals. The conclusion is about the VNO's function in humans, not its development.

c) Although this answer choice provides information about the differences in VNO functioning between humans and other animals, it doesn't directly weaken the conclusion that the VNO is a functioning sensory organ in most humans.

d) This answer choice discusses the absence of secondary anatomical structures associated with the VNO in humans. However, it doesn't directly weaken the conclusion that the VNO is a functioning sensory organ in most humans.

e) This answer choice provides information about the VNO's function in many animal species. However, it doesn't weaken the conclusion that the VNO is a functioning sensory organ in most humans.

In summary, the correct answer choice is (a), as it introduces the possibility of an alternative cause for the subtle smell sensations experienced by the subjects, thus weakening the conclusion that the VNO is a functioning sensory organ in most humans.