In order to reduce   air pollution, many people want a total _____on the playing of firecrackers (鞭炮)in many cities during the Spring Festival.

A．presentation

B．promotion

C． prohibition

D．performance

电荷守恒对应的对称性被称为（）

A、规范变换的不变性

B、空间平移的对称性

C、时间平移的对称性

D、空间的各向同性