Learning to write is learning to think. You don’t know things clearly _________ you can write

them down.

A．unless

B．if

C．since

D．whether

胰腺炎内科治疗无效时应考虑手术，下列哪项不是手术的适应证（）

A.黄疸加深疑有胆管梗阻

B.严重出血急需手术止血

C.腹膜炎经抗生素治疗无效

D.并发脓肿或假性囊肿

E.以上都不是