—David, are you listening to me?

—Sorry, Dad. I ________ to make sense of what the reporter said.

A．was trying

B．have tried

C．am trying

D．tried

慢性皮肤病，有结痂、皲裂、苔藓样变等时，选用：

A．水剂
B．水粉剂
C．软膏
D．油剂
E．粉剂