LSAT Explanation PT 20, S4, Q25: Marianne is a professional chess player

LSAT Question Stem

Which one of the following, if true, most undermines Marianne's argument against the order? 

Logical Reasoning Question Type

This is a Weaken question. 

Correct Answer

The correct answer to this question is D. 

LSAT Question Complete Explanation

In this Weaken question, we are asked to identify the answer choice that most undermines Marianne's argument against the order. Let's first analyze the argument in the passage.

Marianne's argument can be structured as follows:

1. Marianne is unaware of her humming (Premise)

2. Her humming is involuntary because she is unaware of it (Intermediate Conclusion)

3. Therefore, she should not be held responsible for her humming (Main Conclusion)

Our task is to find the answer choice that weakens this argument. Ideally, we want to attack the relationship between the premises and conclusions or undermine the conclusions themselves.

Now, let's evaluate each answer choice:

a) This choice discusses the authority of chess officials outside of matches, which is irrelevant to Marianne's argument about her humming during matches. This choice doesn't weaken the argument.

b) The customs of amateur chess matches are not relevant to Marianne's argument, which is about her behavior as a professional chess player. This choice doesn't weaken the argument.

c) This choice states that not all involuntary actions are actions a person is unaware of. However, Marianne's argument is based on the fact that she is unaware of her humming, and therefore it is involuntary. This choice does not undermine the relationship between unawareness and involuntariness. It doesn't weaken the argument.

d) This choice claims that a person who hums involuntarily can learn to notice and control their humming. If Marianne can learn to control her humming, then it is no longer completely involuntary, which undermines the basis for her argument that she should not be held responsible. This choice weakens the argument and is the correct answer.

e) Whether all or some of Marianne's opponents are distracted by her humming is irrelevant to her argument that she should not be held responsible for her involuntary humming. This choice doesn't weaken the argument.

In summary, the correct answer is D, as it undermines Marianne's argument by suggesting that she can learn to control her humming, making it no longer completely involuntary.