$STATEMENT-1$: For practical purposes,the Earth is used as a reference at zero potential in electrical circuits.
$STATEMENT-2$: The electrical potential of a sphere of radius $R$ with charge $Q$ uniformly distributed on the surface is given by $\frac{Q}{4 \pi \varepsilon_0 R}$.

• A
  $STATEMENT-1$ is True,$STATEMENT-2$ is True; $STATEMENT-2$ is a correct explanation for $STATEMENT-1$.
• B
  $STATEMENT-1$ is True,$STATEMENT-2$ is True; $STATEMENT-2$ is $NOT$ a correct explanation for $STATEMENT-1$.
• C
  $STATEMENT-1$ is True,$STATEMENT-2$ is False.
• D
  $STATEMENT-1$ is False,$STATEMENT-2$ is True.