______ constraint is specified between two relations and is used to maintain the consistency among tuples of the two relations.

______ constraint is specified between two relations and is used to ma

1.	______ constraint is specified between two relations and is used to maintain the consistency among tuples of the two relations.
A.	Entity integrity
B.	Referential integrity
C.	Primary key
D.	Unique key
Answer» C. Primary key

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______ constraint is specified between two relations and is used to maintain the consistency among tuples of the two relations.

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