Her brother _____ be at home now, because he was seen playing basketball in the stadium just now.   [ ]

A. mustn't      

B. needn't    

C. can't    

D. shouldn't

以下各项属于浆细胞肉瘤特点的是（）

A.间歇性或持续性的剧烈疼痛

B.X线表现溶骨性凿孔样缺损

C.本周蛋白尿

D.满天星样改变

E.嗜酸性粒细胞增加