Question

which evidence is most likely used to indicate the beginning of solar system formation?
materials combined to form a mass.
materials were pulled together by gravity.
water condensed and collected to form oceans.
different species of microorganisms lived on earth.

Explanation:

The solar - system formation is thought to have started with the gravitational collapse of a giant molecular cloud. Materials being pulled together by gravity is an early step in this process. The formation of oceans and the presence of microorganisms are related to Earth's development after the solar - system formation. Materials combining to form a mass is a later stage after gravitational attraction has occurred.

Answer:

Materials were pulled together by gravity.