X and Y are two random variable and Z = X + Y. Let σx2, σy2 and σz2 be variance of X, Y and Z. Then

X and Y are two random variable and Z = X + Y. Let σx2, σy2 and σz2

1.	X and Y are two random variable and Z = X + Y. Let σx2, σy2 and σz2 be variance of X, Y and Z. Then
A.	σz2 = σx2 + σy2
B.	σz2 ≤ σx2 + σy2
C.	σz2 < σx2 + σy2
D.	σz2 > σx2 + σy2
Answer» B. σz2 ≤ σx2 + σy2