Assertion (A): Diffraction takes place with all types of waves.
Reason (R): Diffraction is perceptible when the wavelength of the wave is comparable to the dimension of the diffracting device.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is true

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Diffraction takes place with all types of waves."
- This is true because diffraction is a fundamental property of waves, including sound waves, light waves, and water waves. It occurs whenever a wave encounters an obstacle or a slit that is comparable in size to its wavelength.

2. **Understanding the Reason (R)**:
- The reason states that "Diffraction is perceptible when the wavelength of the wave is comparable to the dimension of the diffracting device."
- This is also true. Diffraction effects become noticeable when the size of the obstacle or aperture is on the order of the wavelength of the wave. If the obstacle is much larger than the wavelength, diffraction effects are minimal and may not be observed.

3. **Analyzing the Relationship**:
- While both the assertion and the reason are true, we need to determine if the reason explains the assertion.
- The assertion claims that diffraction occurs with all types of waves, while the reason discusses the conditions under which diffraction is noticeable.
- The reason does not directly explain why diffraction occurs for all types of waves; it only explains when diffraction can be observed.

4. **Conclusion**:
- Since both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion, the correct answer is that both A and R are true, but R is not the correct explanation of A.

### Final Answer:
Both Assertion (A) and Reason (R) are true, but R is not the correct explanation of A.

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