Explanation

(c) Angular momentum of the earth around the sun is
$L = M_{E}v_{0}r$
$\Rightarrow L = M_{E}\sqrt{\frac{GM_{s}}{r}}r\ \ \ \ \ \ \ \left( \because v_{0} = \sqrt{\frac{GM_{s}}{r}} \right)$
$\Rightarrow L = \left\lbrack M_{E}^{2}GM_{s}r \right\rbrack^{1/2}$
Where, $M_{E} =$ Mass of the earth
$M_{s} =$ Mass of the sun
$r =$ Distance between the sun and the earth
$\therefore L \propto \sqrt{r}$