a wedge a pulley an inclined plane a wheel and axle
I gave my students this multiple choice question: A person must lift a heavy load of bricks to the top of a building. Which simple machine is best used for this task?

Only one answer is correct among these 4 choices:
- a wedge
- a pulley
- an inclined plane
- a wheel and axle

Could you tell me which one is correct?

a pulley