A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 trees to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora's extinction. Which of the following, if true, most seriously weakens the argument above?
(A)The drug made from ibora bark is dispensed to doctors from a central authority.
(B)The drug made from ibora bark is expensive to produce.
(C)The leaves of the ibora are used in a number of medical products.
(D)The ibora can be propagated from cuttings and grown under cultivation.
(E)The ibora generally grows in largely inaccessible places.
题目分析：此题巨傻，原文说产药需要一种树，这种树在野外很难得，所以继续生产这种药会导致这种书的灭绝，一看答案就是D，这个选项说我可以人工种这种书，就是说树的来源不仅仅是野生的，可以驳斥。
