The mechanical advantage of any machine is: a) the efficiency of the machine b) the work done by the machine c) the ratio of the work done by the machine to the work expended on it d) the ratio of the force exerted by the machine to the force applied to e) the ratio of the force applied to the machine to the force exerted by it it

Option D) the ratio of the force exerted by the machine to the force applied

Explanation:

The measure of the amplification of the force applied to a mechanical device or a measure of the force exerted by a mechanical device.

The input of the tool or machine is then conserved and the forces are trade off against motion to achieve a required level of amplification.

Therefore, only option c. complies with it.