X、Y均为元素周期表中前20号元素，其简单离子的电子层结构相同，下列说法正确的是(   )

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21394' and id < 1855989 and id<>'1855989' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21394' and id > 1855989 and id<>'1855989' order by id asc limit 5