A student explains the Nebular theory of formation of the solar system as follows.
"The solar system was formed from a slowly rotating cloud called nebula containing extremely cold gases. When these gases were heated up, the nebula contracted and became a flattened disk. As the nebula became smaller, it rotated more rapidly and
became flattened at the poles. Gravitational force caused rings of gases to be left behind when the nebula contracted. At the center of the nebula, the gases combined to form the sun and the planets formed in the outer flattened portion of the disk."
What is the flaw in the student's explanation? (1 point)

1) gravitational forces did not help the nebula to contract
2) the nebula consisted of hot gases which contracted on being cooled
3) the speed of rotation of the nebula decreased when it became smaller
4) planets were formed in the central core of the nebula instead of outer portion
of disk