Answer:
B. Put less work in, get more work out
Step-by-step explanation:
Efficiency means that you want to maximize something with putting little in. With this, the only answer that would make sense would be B.
If you were to put more work in and get less work out that would not be efficient at all. It would be the complete opposite.
If you were to put less work in and get less work out that is still inefficient.
If you put more work in and get more work out that could appear as efficient, but you are still putting in a lot of work which is not efficient.
Thus the best answer would be B. Put less work in, get more work out.
Hope this helps!! Ask questions if you need!