频率调整可以分为一次、二次和三次调节，其中可以实现无差调节的是(    )

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69460' and id < 4498467 and id<>'4498467' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69460' and id > 4498467 and id<>'4498467' order by id asc limit 5