Logical reasoning PrepTest 126 · Section 4 · Question 16

Incorrect. This answer is too strong (All"). We know a lot about horror stories that describe monstrous beasts, but there's no indication that there aren't other types of stories that describe such beasts, and we know nothing about them.

Incorrect. This answer is too strong (Any"). We know that horror stories describe violations of a law of nature, but other types of stories could, as well, and we know nothing about them. (This answer would be correct if it said "Some" such stories, which would be a valid inference from statements 5 and 6.)

Incorrect. This applies only to some horror stories featuring monsters, so this answer is too strong in saying horror stories of any" kind "usually" feature such a description.

Incorrect. First, the stimulus only talks about horror stories with mad scientists, not all stories with mad scientists. Second, characterizing the belief that science can't solve all human problems as antiscientific" isn't necessarily accurate.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
(1) Horror stories—some—Monstrous beasts
(2) Horror stories—some—Mad scientists
(3) Horror stories with monstrous beasts—some—Monster symbolizes psychological issue
(4) Horror stories with mad scientists—most—Express idea that science can't guide all human action
(5) Horror stories → Describe violations of laws of nature
(6) Horror stories → Intended to produce dread

Answer Anticipation:
This Must Be True question has a lot of quantified statements, along with some hidden conditionals. It's not necessarily clear that it's testing these issues out on first read, but the frequent use of quantifier words should have tipped you off!

Let's work through a few of them. First, we split the initial statement into two. We could have represented the initial sentence as a conditional (Horror story → Monstrous beasts OR Mad scientists), but that's a very hard conditional to work with, especially when following statements talk about the two types individually, so it'll be easier to work with as these individual statements. As to why they're some statements, we don't know what percentage fall into each category. Since we can't be certain if it's an even split, or if one of the camps is bigger than the other, we can only say that some fall into each camp.

After that, we get a statement about what is true of some" of one type and most ("typically") of the other. Then, it goes into what's true of both types—and since these two types are comprehensive, this is a conditional statement about all horror stories. That's how we ended up with statements 5 and 6.

With all that written out, we can see that drawing all potential inferences ahead of time is going to be too much—there are just too many. Instead, we should note the strength of inferences we can make and then "backsolve" from the answer by comparing the answers of that strength (or weaker) to the statements to see if we can support it. And because of the set of statements we have, the strongest inference we can draw (other than the contrapositive of those last conditionals) is a some statement.

Answer Explanation:
This answer is supported by the stimulus. We know that some horror stories about monstrous beasts employ symbolism ("the monster symbolizes . . . "). We also know that all horror stories (of either type) describe violations of the laws of nature. Therefore, certain horror stories featuring monstrous beasts employ symbolism and describe violations of the laws of nature, justifying this answer. (Shorter explanation? This is the inference drawn from statements 3 and 5.)

Key Takeaway:
Forget that entire process for this takeaway. When Must Be True questions feature a large number of statements that have overlap, the correct answer will probably combine them. When Must Be True questions feature quantifiers, they'll probably be a part of the combinations. When you make inferences using quantified statements, the resulting inference is almost always a some statements; it's rarely a most statement. Start with those answers and try to justify them instead of trying to anticipate all potential answer choices.