Ⅰ.every non-key attribute is functionally dependent on the full set of primary key attributes.
Ⅱ.no non-key attributes exist in the relation.
Ⅲ.the primary key consists of only one attribute.
A.Ⅰ only
B.Ⅰ and Ⅱ only
C.Ⅰ and Ⅲ only
D.any of them
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