A machine can decrease both the input force and the input distance needed to do a given amount of work.
Explanation:
It's a matter of elimination. The first one is not a bad choice, let's keep looking thoug. The second choice, if it does a little amount of work, than how is it being called useful? Eliminate. Third choice this is the correct answer becasue if you compare it with last and first choice it is the better out of the two.
