Newton's Version of Kepler's Third Law States According to This

Multiple Choice

Newton's version of Kepler's third law states According to this, what observational information does one need in order to calculate the combined mass of a planet and its moon?

A) the orbital period and the density of the two objects
B) the radius of the two planets in meters and the average distance between them
C) the average distance between the two objects and the orbital period
D) It is impossible to determine the mass of any astronomical object.