—of water do you want?—Three.AHow much glass B．How many glasses C．How much

问题补充：

—of water do you want?

—Three.

A．How much glass B．How many glasses C．How much

答案：

解析：glass作为不可数名词使用时，是玻璃。作为可数名词使用时，是玻璃杯。根据答语可知上文句意为，你想要几杯水？故选B。