List-I List-II
a) Fresnel's diffraction e) Bright band
b) Fraunhofer's diffraction f) Source and screen are at finite distance
c) In interference phase difference is even multiple of `pi` g) Dark band
d) In interference phase difference is odd multiple of `pi` h) Source and screen are at infinite distance

Options

A. `A-F, B-H, C-E, D-G`
B. `A-E, B-G, C-F, D-H`
C. `A-H, B-F, C-E, D-G`
D. `A-F, B-H, C-G, D-E`

Answer

To solve the problem of matching elements from List-I with List-II, we will analyze each item in List-I and find the corresponding item in List-II based on the principles of wave optics.

### Step-by-Step Solution:

1. **Fresnel's Diffraction (a)**:
- Fresnel diffraction occurs when the source and the screen are at a finite distance from each other.
- Therefore, we match **a) Fresnel's diffraction** with **f) Source and screen are at finite distance**.

2. **Fraunhofer's Diffraction (b)**:
- Fraunhofer diffraction occurs when the source and the screen are at an infinite distance from each other.
- Thus, we match **b) Fraunhofer's diffraction** with **h) Source and screen are at infinite distance**.

3. **In interference, phase difference is an even multiple of π (c)**:
- An even multiple of π (like 0, 2π, 4π, etc.) corresponds to constructive interference, which results in bright bands.
- Hence, we match **c) In interference phase difference is an even multiple of π** with **e) Bright band**.

4. **In interference, phase difference is an odd multiple of π (d)**:
- An odd multiple of π (like π, 3π, 5π, etc.) corresponds to destructive interference, which results in dark bands.
- Therefore, we match **d) In interference phase difference is an odd multiple of π** with **g) Dark band**.

### Final Matches:
- a) Fresnel's diffraction → f) Source and screen are at finite distance
- b) Fraunhofer's diffraction → h) Source and screen are at infinite distance
- c) In interference phase difference is even multiple of π → e) Bright band
- d) In interference phase difference is odd multiple of π → g) Dark band

### Summary of Matches:
- a → f
- b → h
- c → e
- d → g