You are presented with the question "What can change the movement of something or have it remain stationary?" and the following answer choices: 
- rolling around
 - pulling chains
 - a hydraulic system
 - remaining motionless
 - kinetic energy
 - friction
 - Electrical energy
 - pushes and pulls

Now knowing that if two balanced forces act on an object in opposite directions then that object will remain stationary and pushes and pulls can change the movement of an object, choose the best answer.


 

        pushes and pulls 