Answer:
The label 3
Explanation:
Let's analyze each of the labels until we reach the correct answer.
The label 1 is the force that the person applies to be able to lift the wheelbarrow.
The label 2 is the support of the wheelbarrow, however at that time no forces act on it.
The label 5 shows the distance between the point of application of force and the center of the wheel.
Label 4 shows the center of the wheel of the wheelbarrow.
In this way the label 3 shows the force applying the load on the wheelbarrow.
