There are different kinds of presents in the gift shop. I can’t decide _______.

A．to buy what

B．to buy which

C．what to buy

D．which to buy

蝶鞍CT的最佳扫描方式是（）

A.冠状扫描

B.横断扫描

C.矢状扫描

D.横断扫描+矢状扫描

E.横断扫描多方位重建