If $x+iy=\sqrt{\large\frac{a+ib}{c+id}}$,then the value of $\large\frac{(x^2+y^2)^2(c^2+d^2)}{(a^2+b^2)}$ is

Question

$\begin{array}{1 1}(A)\;x^2+y^2&(B)\;(x^2+y^2)^2\\(C)\;1&(D)\;0\end{array}$