Answer:
C. size; direction
Explanation:
By definition, a machine is referred to any device that makes work easier. It takes force to do work, hence, work refers to the application of force over a particular distance. A machine aims at making the work easy by changing how it is done. Simple machines, which include: levers, pulleys, inclined planes etc. all carry out the same thing, which is to make work easier, by changing the size/magnitude and direction of the applied force.
A simple machine tends to change the size of the inputted force by increasing it over a shorter distance. The machine increases the force applied better than it can be done manually e.g. a plier and nutcracker increases/changes the applied force better than it can be done with bare hands.
Also, a simple machine can achieve making work easier by changing the direction at which the force is applied. The machine applies the force on the object in an opposite direction or contrary to the way it was manually applied.
