Along with the email was my brother’s promise ______ I came first in the competition, he would buy me an MP4.

A．what

B．that

C．that if

D．whether

种子萌发时需要空气，其根本原因是（　　）

A．种子在不停地吸收水分

B．种子在不停地提供营养

C．种子在不停地进行呼吸

D．种子在不停地运输养料