[討論]CD-boldface-3

[訪客]

3. The interstitial nucleus, a sub-region of the brain’s hypothalamus, is typically smaller for male cats than for female cats. A neurobiologist performed autopsies on male cats who died from disease X, a disease affecting no more than 0.5 percent of male cats, and found that these male cats had interstitial nuclei that were as large as those generally found in female cats. Thus, the size of the interstitial nucleus determines whether or not male cats can contract disease X, but, the hypothalamus is known not to be causally linked to disease Y, and disease X is a subtype of disease Y.The two portions in boldface play which of the following roles?
(A) The first is a fact in support of the consideration that is one of two points of this argument; the second is the alternative point that weighs against the first.
(B) The first is an evidence that supports the consideration that the argument includes; the second is the fact that weighs against that consideration that could be drawn from the first.
(C) The first is a general principle that is against the conclusion; the second is that conclusion.
(D) The first is an evidence that supports the conclusion; the second is an exceptional example.
(E) The first is a fact in support of the conclusion that the argument depends on; the second is a fact that is against the first one.





Ans:A
But I can't understand "one of two points of this argument" in A.
What's that???
Very tough question