单选题
A group of scientists demanded that the federal government ____ all the studies it has founded on cloning.
A、
reveal
B、
revealed
C、
is revealing
D、
must reveal
【正确答案】
A
【答案解析】
demanded 要求句子用虚拟，should加动词原形，should 可以省略a. reveal
提交答案
关闭