Logical reasoning PrepTest 133 · Section 2 · Question 21

Incorrect. It would be easy to eliminate this answer because it talks about young singers without great vocal power, and the related stimulus statement is about those who do have great vocal power. However, the stimulus talks about that group using comparative language—they're most likely to ruin their voices, so the group without such power must be less likely to ruin their voices by singing these roles. However, that's not enough to support that they're "unlikely" to ruin their voices. The powerful group might have a 70% chance of ruining their voices, and this group a 60% chance. In jumping from a relative term to an absolute one, this answer is flawed.

Incorrect. The explanation that the author believes isn't the case ("But . . . the real problem"), so this answer is something the opposing point would agree with but isn't supported by the argument.

Incorrect. First, this answer talks about what "should" be done, and the stimulus never uses similar language. Though even if we say that we can support the contention that opera singers shouldn't do something that would destroy their voices, we still can't support this answer. The stimulus notes that the technical training is necessary to avoid straining vocal chords, and there's no indication that "many years" of technical training is necessary to reach that point.

Incorrect. The stimulus notes that "most" young singers lack the training to avoid straining their vocal cords, so there may be some who do have that training and thus could sing these parts without putting undue strain on their voices.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
(1) Opera singer who sings demanding role while young -most-> Lose voices early
(2) Young singers with great vocal power are most likely to lose voices
(3) Real problem - Young singer -most-> Lack training necessary to avoid straining vocal cords
(4) Misuse vocal cords → Truncated singing career

Answer Anticipation:
A lot of moderately strong statements that we have diagrammed out here, so let's start by working through them.

That first statement is a normal most statement.

The second statement we disregarded because it's what some have said, but the author pivots away from this, so it's unlikely that it will lead to an inference.

The following statement brings up a correlation, but it's not a most quantified statement—the group most likely to lose their voices doesn't necessarily see over half of their members lose their voice. To see this, similarly, the person most likely to win the lottery is the person with the most tickets, but that person isn't likely to win.

We then get a note about the real problem, which is another most statement, and then a conditional statement ("invariably") concludes the stimulus.

With that all diagrammed out, can we draw any inferences? There's only a single conditional, so we can't look for a chain. And the terms of the most statements don't line up with those of the other most statements or the conditional.

So where is there overlap? Well, the first statement talks about losing voices early, and the conditional talks about having a truncated singing career. Losing your voice as an opera singer would certainly truncate your singing career, so there's a connection there. Since the stimulus also discusses the "real problem" that leads to it is related to vocal strain, the correct answer might connect those demanding roles to straining the vocal cords.

Answer Explanation:
The "real problem" that leads to an opera singer who adds a demanding role at a young age to lose their voice is the strain on their vocal cords, so it's strongly supported that the majority of this group that loses their voices does so because of strain to their vocal cords. This answer is supported by the stimulus, so it's the correct answer.

Key Takeaway:
When there aren't ways to combine statements in a Must Be True question using formal logic rules, look for statements that overlap. Having a connecting between statements is required to make inferences (similar to inferences between rules in the LG section).