The reason for his absence from school was ____ he fell ill.

A．because

B．why

C．what

D．that

餐饮产品的销售特点为（）

A、经营场所的大小限制了餐饮产品的销售量

B、进餐时间限制了餐饮产品的销售量

C、销售毛利率高，资金周转快

D、成本构成复杂，固定成本高开支比重大