Final answer:
The subject of this question is forces. In part (a) of the figure, we see two ice skaters pushing on a third skater, exerting forces on them. In part (b) of the figure, a free-body diagram represents the forces acting on the third skater.
Thus, the correct option is A.
Step-by-step explanation:
The subject of this question is forces.
In part (a) of the figure, we see an overhead view of two ice skaters pushing on a third. These skaters are exerting forces on the third skater, causing them to move in the direction shown. Forces can be represented as vectors and add like other vectors.
In part (b) of the figure, we see a free-body diagram that represents the forces acting on the third skater. This diagram helps us analyze the forces involved.
Therefore, the correct option is a) Forces