— Mum, I've got a headache.

— You _____ long, dear. Go out and take a break. [ ]

A. had read

B. have been reading

C. are reading

D. read

不符合"棉絮斑"特征的有（）。

A.境界不明显，散在性白斑

B.周围常有小出血点

C.见于视网膜周边部

D.神经纤维肿胀引起

E.呈细胞样小体