wheel and axle inclined plane pulley wedge
I gave my students this multiple choice question: A group of workers needs to move a piano from the second floor of a building. The piano is too wide to fit through the door, so they will lower the piano to the ground through a window. Which tool would be best to help the workers lower the piano from the window?

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

Could you tell me which one is correct?

pulley