Teachers’ advice of ______ stress over the school days must be granted by the headmaster.

A．students to reduce

B．students reducing

C．students reduced

D．students being reduced

经纪类证券公司只能从事单一的（）

A、证券经纪业务

B、证券自营业务

C、证券承销业务

D、证券经纪业务和证券自营业务