A prime attribute of a relation scheme R is an attribute that appears

1.	A prime attribute of a relation scheme R is an attribute that appears
A.	in all candidate keys of R
B.	in some candidate key of R
C.	in a foreign key of R
D.	only in the primary key of R
Answer» C. in a foreign key of R

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A prime attribute of a relation scheme R is an attribute that appears

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