A substance derived from the Madagascar periwinkle, which has proved useful in decreasing mortality among young leukemia patients, is cultivated in China as part of a program to integrate traditional herbal medicine into a contemporary system of health care.
(A) A substance derived from the Madagascar periwinkle, which has proved useful in decreasing mortality among young leukemia patients,
(B) A derivative, which has proved useful in decreasing mortality among young leukemia patients, of the Madagascar periwinkle,
(C) A Madagascar periwinkle derivative, which has proved useful in decreasing mortality among young leukemia patients,(D) The Madagascar periwinkle has a derivative which has proved useful in decreasing mortality among young leukemia patients, that
(E) The Madagascar periwinkle, a derivative of which has proved useful in decreasing mortality among young leukemia patients,
答案是e。。总觉得应该是c..因为是根据原文应该是m的衍生物才useful啊～求解
-- by 会员 saturnor (2010/8/10 22:50:57)