Given below are two statements:
Statement $I$: $RNA$ mutates at a faster rate.
Statement $II$: Viruses having $RNA$ genome and shorter life span mutate and evolve faster.
In the light of the above statements,choose the correct answer from the options given below:

• A
  Statement $I$ is false but Statement $II$ is true.
• B
  Both Statement $I$ and Statement $II$ are true.
• C
  Both Statement $I$ and Statement $II$ are false.
• D
  Statement $I$ is true but Statement $II$ is false.