C-09-Q058mediumsingle_mcqIf ax=by=cza^x = b^y = c^zax=by=cz and b2=acb^2 = acb2=ac, then 1x+1z\dfrac{1}{x} + \dfrac{1}{z}x1+z1 equals:a1y\dfrac{1}{y}y1b2y\dfrac{2}{y}y