Given below are two statements:
$Statement$ $(I)$: Viscosity of gases is greater than that of liquids.
$Statement$ $(II)$: Surface tension of a liquid decreases due to the presence of insoluble impurities.
In the light of the above statements,choose the most appropriate answer from the options given below:

• A
  $Statement$ $I$ is correct but $Statement$ $II$ is incorrect.
• B
  $Statement$ $I$ is incorrect but $Statement$ $II$ is correct.
• C
  Both $Statement$ $I$ and $Statement$ $II$ are incorrect.
• D
  Both $Statement$ $I$ and $Statement$ $II$ are correct.