An Attribute(s) That Functions as the Primary Key of Relation

Multiple Choice

An attribute(s) that functions as the primary key of relation A and as a foreign key in relation B of a relational database ____.

A) must have unique values in both relations
B) must have unique values in relation A
C) must have unique values in relation B
D) must not have unique values in either relation
E) must have unique values in one relation if it has unique values in the other