They _________ the habit of visiting old friends,_________ I think is great.

A．keep on;which

B．keep up;which

C．keep on;as

D．keep up;as 

结合所示图像，该病例的诊断是（）

A.葡萄胎妊娠

B.子宫颈癌

C.退化的纤维瘤

D.宫外孕

E.以上都不是