________ collided and merged, forming planets.

Protosuns
Protoplanets
Extrasolar planets
Planetesimals

Image result for protoplanets

www.universetoday.com

Protoplanets are small celestial objects that are the size of a moon or a bit bigger. They are small planets, like an even smaller version of a dwarf planet. Astronomers believe that these objects form during the creation of a solar system.Aug 9, 2009

he is right

The answer is Plantesimals, Not Protoplanets

Planetesimals