—I rang you at about nine, but there was no reply.

—Oh, that was probably       I was seeing the doctor.

A．why

B．when

C．what

D．that

输血相关性移植物抗宿主病的临床表现不包括（）

A.高热，且热型不规则

B.有消化道症状包括恶心、呕吐、腹泻和腹痛

C.少尿

D.发热1～2天后，面部和躯干皮肤出现红斑和丘疹

E.骨髓抑制致全血细胞减少，出现贫血、出血