acceleration due to gravity for a nearly spherical planet is directly proportional to distance from its centre for a point inside it. True or False?

Suppose we want to find out the gravitational acceleration at a depth h from the surface of the planet. Let the mass of the planet is M and its radius R. 
The gravitational acceleration at this depth is given by,
$g=\frac{G\times {\displaystyle \frac{M}{{\displaystyle \frac{4}{3}}\pi R^3}}\times \frac{4}{3}\pi {\left(R-h\right)}^3}{{\left(R-h\right)}^2}=\frac{GM\left(R-h\right)}{R^3}=\frac{GM\left(1-{\displaystyle \frac{h}{R}}\right)}{R^2}$
It varies linearly with h. So the statement is true.