(2014·东北三校第二次联考)It is shown that men have________as women do on average while driving according to recent statistics.

A．twice as many serious accidents

B．serious accidents as twice many

C．twice serious accidents as many

D．serious accidents as many twice

卵巢生殖细胞肿瘤中最常见的是（）

A.不成熟性畸胎瘤

B.成熟性囊性畸胎瘤

C.胚胎性癌

D.无性细胞瘤

E.内胚窦瘤