The word breakthrough is often used when talking about the newest drug or the next treatment in cancer research．
A. finding
B. being found
C. to be found
D. found
网友回答
A. finding
B. being found
(答案→)C. to be found
D. found
解析：这题考查不定式做定语，当名词被最高级，序数词，the next，the last修饰时，要用不定式做定语，而且the next treatment和find是被动关系，选C，句意是：突破这个词经常在谈到癌症研究中的新药物或是下一个将要发现的疗法时被用到。