Which of These Sentences Describes the Motions of the Particles

Multiple Choice

Which of these sentences describes the motions of the particles in the rings of Saturn?

A) Each of the particles moves in an almost circular Keplerian orbit around the planet.
B) The particles move in randomly oriented elliptical orbits and collide frequently with one another.
C) The particles move in zigzag patterns within the ring system because of interaction with the major moons.
D) The particles all move in concert as if they were a solid sheet because of electrostatic interaction.