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PrepTest 73, Passage 1, Question 3

Transcript

Question three. This question asks what the author asserts about something, which means that it's a Detail question. Specifically, they're asking what the author asserts about mutations of genetic material. Mutations are mostly discussed in the second and third paragraph so that's where we're going to be looking for the information to answer this question.

But let's go answer choice by answer choice and see what we can find. Remember the correct answer to a detailed question must be said in the passage explicitly. The only thing they can do to hide it is to use some synonyms. They can rephrase it slightly but not materially. So answer choice A, the majority of such mutations are not passed on to subsequent generations.

This is a distortion of something the passage says. The passage says that the majority of mutations are non adaptive. Not that they're not passed on. In fact, part of the point of the passage is that non adaptive things do get passed on. So answer choice A is not what they said.

It's a confusion of something they said. Answer choice B. The majority of such mutations occur during periods when mass extinctions take place. They do mention mass extinctions in the fourth paragraph but they don't say that mutations occur more often then than at other times.

Again, they're trying to distract us by bringing up things we know from elsewhere in the passage. But this isn't what they were talking about when they were talking about mutations. So B's not the answer, answer choice C, the majority of such mutations change species behavior, rather than their appearance.

The words behavior and appearance were used in the passage. But at no point did the author compare the two to say that behavior happens more often or appearance happens more often or more likely. A lot of wrong answer choices on the test we could put under the category of irrelevant comparisons. They just grab two random concepts from the passage and compare them hoping that because those concepts seem familiar you'll pick the answer without considering what's actually being said.

So C isn't our answer. Answer choice D, the majority of such mutations have no effect on reproductive success. Now this is what the author said. If you go back and look they say that there are random mutations of genetic material that produce attributes that enhance reproductive success.

And there are others that produce harmful attributes. But then most mutations fall into neither category. So most mutations are neither enhancing success nor hurting success. The majority of them have no effect on success. So answer choice D is what they said. So what's wrong with E?

Well, E says the majority of those mutations occur in larger rather than smaller species. This is for the person who remembers that stuff from the Cretaceous extinctions. We know that small mammals survived because they were small, but not that they mutated more because they were small. Or that they mutated more when they were big.

Mutations weren't connected to size so answer choice E is not what they said, what they said was answer choice D.

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