American English has changed _______ the centuries. There are several reasons _____ this.

A．over, for

B．for, with

C．in, of

D．during, about

《智能变电站合并单元测试规范》规定，合并单元电压并列功能测试要求合并单元输出的两路电压采样值应与母联开关、刀闸及（）刀闸位置向对应。