# McK PST: "IF TRUE, would NOT / LEAST" questions

How to address "Which of the following arguments, if true, would NOT help explain" type of questions:

• First note down clearly what the answer should or should not help explain. If it is the difference between two quantities, then what is this difference: which quantity is larger, by how much, and how does it differ from other quantities provided. If what you need to explain is a trend, then find out whether this trend is upward, or downward, or has some clear patterns.
• Go through each option one-by-one, rather than trying to jump onto the correct answer
• For each option, ask yourself the question: can this information explain the issue discussed in this question? If you think it does, write down (in a simple way) how this argument would help explain the issue. For example, write something like "the information has to explain why this quantity is decreasing over time, and this particular information would indeed lead to a decrease in this quantity". This is where you should be careful about the words used in the argument, what precisely do they refer to: current changes or future changes, changes to quantities that are related to the question, but might not directly affect it, etc.
• Try to find reasons why the argument could explain the opposite trend (or quantity, or difference) as the one in the question. If you find some reasons, then this might be a candidate for the argument that would NOT help explain the issue. If you cannot find any counter-reason, then this might be an argument that DOES help explain the issue.
• Once you have eliminated all options that clearly do explain the issue, and could not support a different trend, then you need to compare the remaining options. If some of them, could just never help explain the issue, then this is correct. If all of them could explain it under some conditions, then decide which of these conditions seem more reasonable to you, and eliminate those.
• Remember, however that you should not judge the option based on how reasonable you think it is to assume that the argument is true, since the question asks to assume that it is true.
• For questions of the type "IF TRUE", I think the most important thing is to make sure that you do not try to answer the questions using your own knowledge and experience, but focus on what logically makes sense, even if you believe that the statement which you are told to assume is true is incorrect.
• One approach to take is to ask yourself the following question after you have picked an answer: does the option you have picked implies the statement described in the question? Often the statement in the question will be something like "explain the differences between quantity X and quantity Y", so a good starting point is to ask yourself and write down what that difference is. For example, you could write down something like: "I need to explain why quantity X grew twice as fast as quantity Y in the last two years". Then once you have picked an option, ask yourself: does the explanation in the option imply that quantity X grew twice as fast as quantity Y?".
• You can use a similar approach for questions that ask you what is the "LEAST" likely correct explanation among different statements. Find out what the statement is supposed to explain, and check for each option which would indeed lead to the situation described in the question. The one that does not seem to clearly lead to that situation will be the least likely to be a correct explanation, and therefore the correct answer.