Choose the correct option for each question. There is only one correct response for each question.
Which force always opposes the motion of an object?

Options

A. Frictional force
B. Muscular force
C. Gravitational force
D. Electrostatic force

Answer

To solve the question, we need to identify which force always opposes the motion of an object. Let's analyze the options given.

### Step-by-Step Solution:

1. **Understanding the Forces**: We need to examine the different forces mentioned in the options—Frictional force, Muscular force, Gravitational force, and Electrostatic force.

2. **Analyzing Frictional Force**:
- The frictional force is defined as the force that opposes the relative motion of two surfaces in contact.
- For example, if you try to push a block across a surface, the frictional force will act in the opposite direction to your push, resisting the motion.

3. **Analyzing Muscular Force**:
- Muscular force is the force exerted by muscles. It can either support or oppose motion depending on the situation. For instance, when you push an object, muscular force aids in its motion.

4. **Analyzing Gravitational Force**:
- Gravitational force acts on objects due to gravity. It can support motion (like a falling object) or oppose it (like when you throw an object upwards). Thus, it does not always oppose motion.

5. **Analyzing Electrostatic Force**:
- Electrostatic force can also either attract or repel objects depending on their charges. Therefore, it does not consistently oppose motion.

6. **Conclusion**: Based on the analysis, the only force that consistently opposes the motion of an object is the **Frictional force**.

### Final Answer:
The correct option is **Frictional force**.

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