The manager put forward a suggestion（）we should have an assistant. There is too much work to do.

A. whether

B. that

C. which

D. what

下列对木兰科树种冬态描述不正确的是（）。

A、有长短枝之分

B、叶痕互生，枝条节部有环状托叶痕

C、顶芽发达，近柄芽

D、叶迹为单迹多叶隙