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OFFICIAL SOLUTIONS

Q1.

(D) is correct, as it is the only choice that reflects the idea that men and women have approximately the same number of active genes. Even though men have two different chromosomes, and even though women have a partially inactivated X chromosome, “women are not significantly less genetically complex than men.”

(A) is a faulty use of a detail found in the passage. The author mentions sex-linked genetic defects later in the passage, but the corrosion of the Y chromosome it is not used to explain this fact.

(B) distorts a detail found in the passage. Women have two X chromosomes, not one.

(C) is a faulty use of a detail found in the passage. While this fact about expression heterogeneity is true, it is from a different part of the passage, and does not relate to the corrosion of the Y chromosome.

(E) is yet another faulty use of detail, as facts about genetic diversity are discussed later on in the passage and don't relate to the corrosion of the Y chromosome.

Q2.

(B) is correct. The researcher found precedent, as expected, but found much more of it than expected.

(A) begins well, with the business manager finding some of the economic basis he expected. But (A) also has the business manager finding some evidence countering his plan. This is not parallel to the scientist scenario in paragraph two.

(C) has the historian finding only evidence that is against what he expected, or hoped for.

(D) is incorrect because it doesn't deal with the doctor’s expectations, just what she found. The logic in paragraph two consists of both the scientists' expectations and their findings.

(E) is incorrect because it doesn't relate any of the results of the investigation.

Q3,

(A) is supported by the third paragraph, which states that more evolved genes are expressed at higher levels in women than in men. Thus, such a gene is less likely to be expressed in men than women. (A) is therefore incorrect.

(B) is supported by the passage, and so is incorrect. The last paragraph describes how researchers hope to use the findings about female genetics to "build on their understanding" of genetic defects in men. Therefore there must be a link between the two.

(C) is supported by the end of paragraph three, where the author reports that genetic material is "startlingly diverse" among women, but not among men. Thus, between two randomly chosen men and two randomly chosen women, one would expect more genetic similarities between the men. Since (C) is supported, it is incorrect.

(D) is supported by the third paragraph, and is therefore incorrect. Paragraph three mentions the "imbalanced birth rate between boys and girls" in the context of women's extra X chromosome providing "backup genetic data" that can "mitigate sex-linked genetic defects in females." In this context, it can be inferred that the imbalanced birth rate means more girls are born than boys.

(E) is not supported in the text, and is therefore the correct answer. While the last paragraph asserts that the work described in the passage may "contribute to an explanation of the elusive behavioral and social differences" between men and women, there is nothing in the passage to suggest genetics account for most of those differences.