The mass density of a spherical galaxy varies as \( \frac{\mathrm{K}}{\mathrm{r}} \) over a large distance \( r \) from …

The mass density of a spherical galaxy varies as \( \frac{\mathrm{K}}{\mathrm{r}} \) over a large distance \( r \) from it's centre. In that region, a small star is in a circular orbit of radius \( \mathrm{R} \). Then the period of revolution, \( \mathrm{T} \) depends on \( \mathrm{R} \) as

[JEE Main 2020, 2 Sep (Shift 1)]