Many plant varieties used in industrially developed nations to improve cultivated crops come from less developed nations. No compensation is paid on the grounds that the plants used are “the common heritage of humanity.” Such reasoning is, however, flawed. After all, no one suggests that coal, oil, and ores should be extracted without payment.

Which of the following best describes an aspect of the method used by the author in the argument above?

(A) The author proceeds from a number of specific observations to a tentative generalization.

(B)The author applies to the case under discussion facts about phenomena assumed to be similar in some relevant respect.

(C) A position is strengthened by showing that the opposite of that position would have logically absurd consequences.

(D) A line of reasoning is called into question on the grounds that it confuses cause and effect in a causal relation.（B）

(E) An argument is analyzed by separating statements of fact from individual value judgments.

这题B对，可以理解，但C就不对吗？我觉得C的确是author论证时用的方法呀。谢谢！

The logic of the passage deploys that the free use of crops in

indistrial nations might be unreasonable because the natural energy

cannot be extracted freely. The statement commits a fallacy of "false

analogy" as B claims.

个人认为，作者的意思是说，没人说不付费就可以使用coal,oil等。说plant

varieties的使用也是付费的，而不是free.两个例子是在比较相似之处。

而C表示的则是相反的意思。