For three sets A, B and C, if n(A) = 20, n(B - A) = 16 and
n( C - (A $$\cup$$ B)) = 24, then n(A $$\cup$$ B $$\cup$$ C) =
(n(A) denotes the number of elements in A )

A

56

B

64

C

60

D

48