$A$ spherical insulating ball and a spherical metallic ball of the same size and mass are dropped from the same height. Choose the correct statement out of the following (Assume negligible air friction).

• A
  Time taken by them to reach the earth's surface will be independent of the properties of their materials.
• B
  Insulating ball will reach the earth's surface earlier than the metal ball.
• C
  Both will reach the earth's surface simultaneously.
• D
  Metal ball will reach the earth's surface earlier than the insulating ball.