A granite rock located at the Earth's surface has density $\rho$. It is then moved to the surface of a different planet. The acceleration of free fall at the surface of the other planet is 2 times the value at the Earth's surface. What is the density of the rock on the other planet?
- A$0.5\rho$
- B$\rho$
- C$2\rho$
- D$4\rho$