对于幼儿园的孩子，下列属于二级强化物的有（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='23631' and id < 2055993 and id<>'2055993' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='23631' and id > 2055993 and id<>'2055993' order by id asc limit 5