下面的表达式，（     ）是指电压控制的受控源。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68474' and id < 4421094 and id<>'4421094' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='68474' and id > 4421094 and id<>'4421094' order by id asc limit 5