标志性词语：strengthen、support、provide the best evidence
Astronomer: Most stars are born in groups of thousands, each star in a group forming from the same parent cloud of gas. Each cloud has a unique, homogeneous chemical composition. Therefore, whenever two stars have the same chemical composition as each other, they must have originated from the same cloud of gas.
Which of the following, if true, would most strengthen the astronomer’s argument?
(A) In some groups of stars, not every star originated from the same parent cloud of gas.
(B) Clouds of gas of similar or identical chemical composition may be remote from each other.
(C) Whenever a star forms, it inherits the chemical composition of its parent cloud of gas.
(D) Many stars in vastly different parts of the universe are quite similar in their chemical compositions.
(E) Astronomers can at least sometimes precisely determine whether a star has the same chemical composition as its parent cloud of gas.
Advertising by mail has become much less effective, with fewer consumers responding. Because consumers are increasingly overwhelmed by the sheer amount of junk mail they receive, most discard almost all offers without considering them. Thus, an effective way for corporations to improve response rates would be to more carefully target the individuals to whom they mail advertising, thereby cutting down on the amount of junk mail each consumer receives.
Which of the following, if true, would most support the recommendation above?
(A) There are cost-effective means by which corporations that currently advertise by mail could improve response rates.
(B) Many successful corporations are already carefully targeting the individuals to whom they mail advertising.
(C) Any consumer who, immediately after receiving an advertisement by mail, merely glances at it, is very likely to discard it.
(D) Improvements in the quality of the advertising materials used in mail that is carefully targeted to individuals can improve the response rate for such mail.
(E) Response rates to carefully targeted advertisements by mail are considerably higher, on average, than response rates to most other forms of advertising.