疣状黄瘤中特征性的细胞是（）

A.浆细胞

B.淋巴细胞

C.泡沫细胞

D.组织细胞

E.瘤巨细胞

Though suffering constant noise from the outside world, little Tommy was still working with all his

attention _____ on his unfinished warship model.

A．focusing

B．concentrating

C．fixed

D．looking