Which Observation Supports the Theory That the Planets Formed from a Disk

Multiple Choice

Which observation supports the theory that the planets formed from a disk shaped nebula?

A) Pluto and comets follow elliptical orbits that pass inside the orbit of Neptune.
B) The Sun is the center of the solar system.
C) The rocky planets are close to the Sun.
D) The planets revolve around the Sun in approximately the same plane of the ecliptic.