Satellites orbiting the earth have finite life and sometimes debris of satellites fall to the earth. This is because,
of viscous forces causing the speed of satellite and hence height to gradually decrease.
As the total energy of the earth satellite of radius R bounded system is negative (-GM\2 a) where M is mass of the earth and a is the radius of satellite.
Due to the viscous force acting on satellite, energy decreases continuously and radius of the orbit or height decreases gradually.
Final Answer:(c)