What prevents the gravity of the sun to pull all of the planets towards it?

Question

the size and shape of the planets around the sun
the planets' speed as they orbit the sun
the sun's weak gravity
the large distance of the planets from the sun

Answer 1

The correct answer is: the planets' speed as they orbit the sun.

The gravitational force from the sun indeed acts as an attractive force on the planets, trying to pull them inward. However, the planets' orbital speed counteracts this gravitational force and keeps them in stable orbits. The balance between the gravitational force and the centrifugal force generated by the planets' orbital speed keeps them in their respective orbits around the sun. The size and shape of the planets, the sun's gravity, and the large distance of the planets from the sun also play a role, but the primary factor that prevents the planets from falling into the sun is their orbital speed.