Imagine a light planet revolving around a very massive star in a circular orbit of radius r with a period of revolution T. On what power of r will the square of time period will depend if the gravitational force of attraction between the planet and the star is proportional to `r^(-5//2)`.
A. `T^(2) alpha R^(5//2)`
B. `T^(2) alpha R^(-7//2)`
C. `T^(2) alpha R^(3//2)`
D. `T^(2) alpha R^(4)`
