The number of the people invited to the meeting ____ about 100, but a number of them ____ late because of the heavy snow.

A．were; was

B．were; were

C．was; were

D．was; was

会游泳的同学都有过这样的体会，刚下水时，水超过胸部会感到呼吸吃力，对此合理的解释是（　　）

A．不熟悉水性心理紧张

B．水的压力使胸阔扩大受阻

C．水中含氧少

D．水中温度低