If n(A)=10, n(B)=30,n(C)=50 and if set A, B, C are pairwise disjoint then which of the following is correct?

If n(A)=10, n(B)=30,n(C)=50 and if set A, B, C are pairwise disjoint t

1.	If n(A)=10, n(B)=30,n(C)=50 and if set A, B, C are pairwise disjoint then which of the following is correct?
A.	n(A U B)=0
B.	n(B U C)=0
C.	n(A U B U C)=90
D.	All of the mentioned
Answer» E.

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