It is widely believed among bioengineers it will be possible to create life under laboratory conditions．
A. which
B. what
C. that
D. when
网友回答
A. which
B. what
(答案→)C. that
D. when
解析：四个选项分别表示哪一个、什么、那个和什么时候。根据题意,生物工程师中普遍认为,在实验室条件下有可能创造生命.从句内容对前面整句话进行修饰说明,故只能选C,that指代整句话.