Masses of the Planets Are Easiest to Determine If

Multiple Choice

Masses of the planets are easiest to determine if:

A) they are terrestrial and the extra size of the planet's disk can be measured.
B) they are jovian and their oblateness can be found.
C) they have natural satellites whose motions can be precisely measured.
D) they are dense and easily deflect the path of passing spacecraft.
E) they move rapidly and their periods are easily measured.