Let a binary operation '*' be defined on a set A. The operation will be commutative if

A.

a*b = b*a

B.

(a*b)*c = a*(b*c)

C.

(b ο c)*a = (b*a) ο (c*a)

D.

None of the above

Correct answer is A

A binary operation '*' defined on a set A is said to be commutative only if a*b=b*a, ∀a, b∈A. If (a*b)*c=a*(b*c), then the operation is said to associative ∀ a, b∈ A. If (b ο c)*a=(b*a) ο (c*a), then the operation is said to be distributive ∀ a, b, c ∈ A.