Why is A a better answer choice over E?

@JeremyG, Happy to help. This is a strengthen with a necessary premise question, so we're looking for the answer choice that, if false, makes the argument fall apart. We can use the negation test to see if an answer choice that's negated wrecks the argument. If it does, then it's the correct answer. (A) says, "Supporters of tariffs on particular products are not significantly more likely than opponents to base their vote for a politician on the politician's stand on this issue." (A)'s negation is "Supporters of tariffs on particular products are significantly more likely than opponents to base their vote for a politician on the politician's stand on this issue." If supporters of tariffs are far more likely than opponents to base their vote on a politician's stance on tariffs (that is, a single issue), then this argument falls apart because it doesn't matter that most people oppose tariffs because they might not even be voting based on the politician's stance on tariffs. Thus, (A) has to be true in order for this argument to have a chance, so it's the correct answer choice. (E) says, "People who would be hurt by tariffs generally know that they would be hurt by them." (E)'s negation is "People who would be hurt by tariffs do not generally know that they would be hurt by them." The thing is, we already know from our premises that most people do oppose tariffs. We do not need to know their reasons for opposing tariffs. Even if people do not know they would be hurt by tariffs, we already know that most people still oppose them. (E)'s negation doesn't wreck the argument, so this answer choice isn't a necessary premise. We can get rid of it. Does this make sense? Let us know if you have any more questions!

Yes that clears it up, thank you!

@JeremyG, great! Let us know if you have any other questions!

@Ravi With respect to your explanation regarding the elimination of Answer (E), Isn't it the case that we know that those who oppose tariffs do so because it would hurt them? This is to say that if they didn't know it was hurting them, they may or may no oppose the tariffs.