Pick your answer from: 1. Lift 2. kinetic 3. weight 4. motion 5. speed 6. direction 7. color 8. muscles

You are presented with the quiz "pushing and pulling an object will increase its what" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "force causes the speed of an object to increase" and "pulling and pushing is forceful motion". So, what's the best answer to the question?
Answer:
5.