The airport ___next year will help promote tourism in this area.

A．being completed

B．to be completed

C．completed

D．having been completed

若调查某偏远农村摄入食物与夜盲症的关系，在设计食物频率法调查表时，首先应选择的食物是（）

A、菠菜

B、猪肝

C、牛奶

D、鸡蛋