If x , y , z are in GP then , $\;\large\frac{1}{x^2-y^2}+\frac{1}{y^2}\;$ equals

Question

$(a)\;\large\frac{1}{z^2-y^2}\qquad(b)\;\large\frac{1}{y^2-z^2}\qquad(c)\;\large\frac{1}{z^2-x^2}\qquad(d)\;\large\frac{1}{y^2-x^2}$