Question Type:
Match the Principle
Stimulus Breakdown:
Vaccines have a weak disease in them, which is going to help the patient.
Answer Anticipation:
The principle at play here is "immunity." Normall, I wouldn't sum it up in one word, but that's the most succinct way to describe what's going on, so I want to find an answer that has a similar immunity (though I'm expecting it to be in a field other than medicine).
Correct Answer:
(B)
Answer Choice Analysis:
(A) Tempting. This answer makes a recommendation that sounds bad (don't rehearse) to bring about a benefit. However, the "not rehearsing" isn't a watered down version of "forgetting lines", so this doesn't convey the idea of immunity.
(B) Bam. Parents are making their kids immune to treachery/cruelty by exposing them to a weaker form.
(C) Tempting. This answer has a similar idea in that something is being used to fight a version of itself (weak virus vs. later exposure). However, the explosion isn't a "weaker" version of fire, and the fight is happening at the same time (explosion vs. fire happening right now) instead of later on. The explosion isn't preventing future fires.
(D) This answer is more akin to cutting off a rotting limb (sorry for the gross analogy, but the question sets it up!) than creating immunity.
(E) Tempting! A lot of tempting answers in this question. However, the police aren't introducing minor crime to prevent bigger crimes, which is what would be needed to match up with the initial situation. The principle here is more "nipping something in the bud" rather than immunity.
Takeaway/Pattern:
Succinctly defining the principle up front is the most important part of nailing these questions. However, sometimes you'll have to go back to the initial argument to check individual parts of the answer to see if they match up, and that's okay.
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