Which pregnancy-related physiologic change would place the client with a history of cardiac disease at the greatest risk for developing severe cardiac problems

A．Decreased heart rate.

B．Decreased cardiac output.

C．Increased plasma volume.

D．Increased blood pressure.

有对箱式变电站产生破坏性的自然现象和气候（如大风、雷雨、地震等）及其他异常情况（如 电缆线路有可能被施工、运输、爆破等原因破坏）时应进行特巡。