What role did gravity play in forming the sun?

Gravity caused the solar nebula to collapse toward the center, causing the center of the sun to be dense and hot.

Gravity turned the protoplanetary disk into a planetesimal, which became the sun.

Gravity turned the protoplanetary disk into a rotating solar nebula, which became the sun.

Gravity caused small particles to collide to form larger particles called planetesimals, which eventually formed the sun.