—It’s a pity that Wang Qiang failed in the driving test again.

—How can you expect him to pass _______ he hasn’t been practicing enough?

A．when

B．once

C．unless

D．though

中国工农红军第一支坚强的队伍是中国工农红军[ ]

A、第一军

B、第二军

C、第四军

D、第六军