So many problems ________， he is having a difficult time.

A．settled

B．to settle

C．settling

D．are to settle

急进性肾小球肾炎的预后与下列哪项因素关系极为密切（）

A.高血压

B.少尿

C.水肿

D.肾小球新月体的数量

E.血尿