$S$ Statement: $Halophilus$ is responsible for the production of biogas. $R$ Statement: $Halophilus$ is an example of the $Bacteria$ domain.

• A
  $S$ and $R$ are both true,and $R$ is the correct explanation of $S$.
• B
  $S$ and $R$ are both true,but $R$ is not the correct explanation of $S$.
• C
  $S$ is true and $R$ is false.
• D
  $S$ and $R$ are both false.