A solid iron sphere A rolls down an inclined plane, without slipping while an identical sphere B slides down the plane in a frictionless manner. At the bottom of the inclined plane, The total kinetic energy of sphere A is

• A

  less than that of B

• B

  equal to that of B

• C

  more than that of B

• D

  less than B if angle of inclination of the plane is less than ${45}^{\mathrm{o}}$