- Gravity causes objects that have mass / substances to be pulled down / to fall on a planet
- Gravity is a kind of force
- A ball is a kind of object
- So, gravity is the force that pulls the ball towards the planet

Hence, gravity is the force that pulls the ball towards the planet
[Question]A student tosses a ball into the air. Which force causes the ball to fall back to the ground?
[Context]- Gravity causes objects that have mass / substances to be pulled down / to fall on a planet 
- Gravity is a kind of force 
- A ball is a kind of object