请看下表:
Books
------
BookId
BookName
AuthorId
SubjectId
PopularityRating (the popularity of the book on a scale of 1 to 10)
Language (such as French, English, German etc)
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Subjects
---------
SubjectId
Subject (such as History, Geography, Mathematics etc)
/////////////////////////////////////////
Authors
--------
AuthorId
AuthorName
Country
哪项查询可确定至少写过一本受欢迎程度低于 5 分的书的作者？( )
select authorname from authors where authorid in (select authorid from books where popularityrating<5)
select authorname from authors where authorid in (select authorid from books where popularityrating<=5)
select authorname from authors where authorid in (select BookId from books where popularityrating<5)
select authorname from authors where authorid in (select authorid from books where popularityrating in (0,5))
