Which of the following statements about the rings of the four jovian planets is not true?

.All are made of individual particles of rock or ice that orbit in accord with Kepler's laws: inner ring particles orbiting faster, and outer ring particles orbiting slower.

b.All have gaps and ringlets, probably due to gap moons, shepherd moons, and orbital resonances.

c.All probably look much like they did when the solar system first formed.

d.All the particle orbits are fairly circular, near their planet's equatorial plane.