恶性卵巢肿瘤的诊断依据是（）

A.根据患者年龄、病史特点及局部体征可初步诊断

B. * * 脱落细胞涂片查找癌细胞

C.B超检查可确诊

D.可用腹部X线平片进行确诊

E.从腹水中找癌细胞

She _____ be at home because I saw her here just now.                                                                         [ ] 

A.doesn't                                                          

B.mustn't                                                          

C.can't                                                            

D.needn't