Answer:
It allows a smaller force to be applied over a longer distance.
Step-by-step explanation:
A ramp is an example of an inclined plane that makes the movement of object easier above the ground level or higher surfaces.
In the given example, the sloping part of the ramp will support the weight of the piano as it moves up the slope and it will allow less force to be applied to move the piano above but the distance would be longer as the slant length or slope is the longest distance.
Hence, the correct answer is "d".