Assertion : Use of ball beaings between two moving parts of a machine is a common practice.
Reason : Ball bearings reduce vibrations and provide good stability.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion.
B. if both assertion and reason are true but reason is not the correct expalanation of the assertion
C. if assertion is true , but reason is false
D. both assertion and reason are false statements.

Explanation

To solve the question, we need to analyze the assertion and the reason provided, and determine their validity.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Use of ball bearings between two moving parts of a machine is a common practice."
- This is true. Ball bearings are widely used in machinery to facilitate smooth movement between parts.

2. **Understanding the Reason**:
- The reason states that "Ball bearings reduce vibrations and provide good stability."
- While it is true that ball bearings can help in reducing vibrations to some extent, their primary purpose is to reduce friction. The assertion does not specifically mention vibration reduction or stability as the main reason for using ball bearings.

3. **Analyzing the Relationship**:
- The assertion is true, but the reason is misleading. The primary function of ball bearings is to reduce friction between moving parts, which in turn can lead to less wear and tear and potentially less vibration, but this is not the main reason for their use.

4. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- **Assertion**: True
- **Reason**: False
- Therefore, the correct option is that the assertion is true but the reason is false.

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