Given two relations R1(A, B) and R2(C, D), the result of following querySelect distinct A, Bfrom R1, R2is guaranteed to be same as R1 provided one of the following condition is satisfied.

R1 has no duplicates and R2 is non-empty.

R1 has no duplicates and R2 is empty.

Both R1 and R2 have no duplicates.

R2 has no duplicates and R1 is non - empty

Given two relations R1(A, B) and R2(C, D), the result of following que

1.	Given two relations R1(A, B) and R2(C, D), the result of following querySelect distinct A, Bfrom R1, R2is guaranteed to be same as R1 provided one of the following condition is satisfied.
A.	R1 has no duplicates and R2 is empty.
B.	R1 has no duplicates and R2 is non-empty.
C.	Both R1 and R2 have no duplicates.
D.	R2 has no duplicates and R1 is non - empty
Answer» B. R1 has no duplicates and R2 is non-empty.

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