In walking, identify the force of reaction:

Options

A. push of our foot on the ground
B. push of ground on our foot
C. either (a) or (b)
D. neither (a) nor (b).

Explanation

To identify the force of reaction in walking, we can break it down into a few steps:

### Step-by-Step Solution:

1. **Understanding Action and Reaction Forces**:
- According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. This means that when we exert a force in one direction, there is a force exerted back in the opposite direction.

2. **Identifying the Action Force in Walking**:
- When a person walks, they exert a force downwards and backwards against the ground with their feet. This force is known as the action force.

3. **Identifying the Reaction Force**:
- The ground responds to the force exerted by the foot. According to Newton's Third Law, the ground exerts an equal and opposite force back on the foot. This force is known as the reaction force.

4. **Conclusion**:
- Therefore, in the context of walking, the action force is the force exerted by the foot on the ground, and the reaction force is the force exerted by the ground back on the foot.

### Final Answer:
In walking, the force of reaction is the force exerted by the ground on the foot, which acts in the opposite direction to the force exerted by the foot on the ground.

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