Final answer:
The net force acting on an object in a free-body diagram is the vector sum of all forces acting on it. This could be any of the vectors a, b, c, d, e, based on their directions and magnitudes.
Step-by-step explanation:
A free-body diagram is a representation of a single object within a system with vectors representing forces acting on it. In this particular case, we would need the actual diagram to make a conclusive decision. However, the direction of the net force acting on an object is determined by taking the vector sum of all the individual forces acting on the object. If these forces are represented by vectors a, b, c, d, and e in the diagram, the vector that best represents the direction of the net force is typically the resultant vector after adding all these force vectors together, assuming no equilibrium condition.
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