Suppose the gravitational force varies inversely as the $$n$$th power of distance. Then the time period planet in circular orbit of radius $$R$$ around the sun will be proportional to

A

$$R^{\left(\frac{n+1}{2}\right)}$$

B

$$R^{\left(\frac{n-1}{2}\right)}$$

C

$$R^n$$

D

$$R^{\left(\frac{n-2}{2}\right)}$$