Which statement best describes why a machine is useful?

a-a machine does a greater amount of work than the amount of work that is done on it.
b-a machine does a smaller amount of work than the amount of work that is done on it.
c-a machine can decrease both the input force and the input distance needed to do a given amount of work.
d-a machine can decrease either the input force or the input distance needed to do a given amount of work.

Answer;

D-A machine can decrease either the input force or the input distance needed to do a given amount of work.

Explanation;Machines or simple machines are devices that make work easier by reducing, multiplying, or changing the direction of a force. These machines includes; lever, inclined plane, pulleys, wheel and axle, etc.Machines can reduce either the input force or the input distance needed to do a given amount of work. Additionally, machines can not change the amount of work being done, but, they reduce the effort force which is required for work to be done.

It is d, all the other ones say incorrect answer .