C-05-Q117mediumsingle_mcqWhich of the following is an identity?a(x+1)2+(x−1)2=4x(x + 1)^2 + (x - 1)^2 = 4x(x+1)2+(x−1)2=4xb(x+1)2+(x−1)2=2(x2+1)(x + 1)^2 + (x - 1)^2 = 2(x^2 + 1)(x+1)2+(x−1)c(a+b)2+(a−b)2=2ab(a + b)^2 + (a - b)^2 = 2ab(a+b)2+(a−b)2=d(a−b)2=a2+2ab+b2(a - b)^2 = a^2 + 2ab + b^2(a−b)2=a2+2ab+