下列关于比例税率的叙述中不正确的是( )。

A．同一课税对象按一个百分比的税率课税

B．计算简便，征收率高

C．是我国应用最广泛的一种税率形式

D．遵循能量纳税原则

During the day，a dredge will indicate the side on which it is safe to pass by displaying（）.

A.two balls in a vertical line

B.two diamonds in a vertical line

C.a single black ball

D.no shape is shown during the day