下列物质一定属于同系物的是（  ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21930' and id < 1914184 and id<>'1914184' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21930' and id > 1914184 and id<>'1914184' order by id asc limit 5