排卵前LH峰（）

A.其值小于FSH峰值

B.在促排卵周期中不产生

C.由于雌二醇急剧升高诱发

D.促使颗粒细胞大量生成睾酮

E.诱发排卵立即发生

—What a pity! Their experiment is a failure.

—They ________ better under more favorable conditions.

A．should have done

B．could have done

C．must have done

D．may have done