ZP?W1-18型无绝缘移频自动闭塞, 站内功放盒功出电压( )。[321010104]
A.AC18.0V~35.0V
B.DC18.0V~35.0V
C.AC20.0V~40.0V
D.DC20.0V~40.0V
正确答案是A