Homomorphism:- let G and G' be two group and there exit a mapping function f: G--->G' said to be Homomorphism.
if f(a O b)-----> f(a) O' f(b) where a and b belong to G and f(a) and f(b) belong to G.
"The set of all the elements of G is mapped to the identity element of G' under the mapping f"
In the question, we have to find those whose which satisfied the homomorphism and as well as satisfied the kernel properties also
