I regret ______ you that you have not been chosen for the performance.

A．telling

B．to tell

C．having told

D．to be telling

下列化学药品的保存方法不必要的是                       

A．少量白磷保存在水中

B．盛苯酚晶体的试剂瓶要密封

C．铝片要隔绝空气密封保存

D．盛溴的试剂瓶中加入一些水