As it is presented in the passage, the approach to history taken by mainstream U.S. historians of the late nineteenth...

Irina on November 19, 2019

@joseorellana,

The question asks us if during one week Jerry drives on W and S only, then which of the following must be true?

H J J
M T W Th F S

We can infer that neither G nor F can drive on M, therefore H must drive on M (C).
Since it is a must be true question, a correct answer choice must be true in every scenario, whereas an incorrect answer choice is either must be false or could be true in one or more scenarios but also could be false in others.

(B) G drives on T

It is true that G could drive on T, but it is also possible for G to drive on Th or F for example:

H F J G H J
M T W Th F S

Since we can come up with a schedule where (B) is not true, (B) is incorrect.

(D) F drives on exactly two days,

Again, this could be true - he could drive on T and Th or T and F for example, but it also could be false as in our hypothetical schedule above.

(E) H drives on exactly two days.

This could be true, but could be false, instead, F or G could drive on exactly two days:

H F J G F J
M T W Th F S

Therefore, we can eliminate (B), (D), and (E). Only (C) must be true in every scenario for the schedule to comply with all the rules.

Let me know if you have any other questions.