在连接电路的过程中,下列几种做法中,没有必要的是:A.断开开关按

在连接电路的过程中,下列几种做法中,没有必要的是:

A.断开开关按电路图连接元件;

B.开关必须靠近电源的正极;

C.各个接线点一定要连接牢固;

D.全部连接完后,再对照电路图检查,无误后再闭合开关.

答案

B

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