This problem is easy when you remember the example gone over in class.
Firstly P(A=1)=1/2 P(B=1)=p C = A xor B
The way i did it was to prove whether P(C=1|A=1)= P(C=1)*P(A=1)
Also P(C=1|A=1) = P(B=0) = 1-p
find P(C=1) and multiply it by P(A=1) and check if it is equal to 1-p
