— Shall we go boating this afternoon?

— It depends on the weather. I will go _____ it rains and the wind blows hard.[ ]

A. when

B. until

C. as

D. unless

预授权类交易只有进行（）操作，特约商户才能收到交易款项。

A、预授权

B、预授权撤销

C、预授权完成

D、预授权完成撤销