`X`-rays are produced by jumping of:

Options

A. electrons from lower to higher energy orbit of atom
B. electrons from higher to lower energy orbit of atom
C. protons from lower to higher energy orbit of nucleus
D. protons from higher to lower energy orbit of nucleus

Answer

To solve the question of how X-rays are produced, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding X-ray Production**:
X-rays are a form of electromagnetic radiation. They are produced when high-energy electrons collide with a target material, typically in an X-ray tube.

2. **Electron Energy Levels**:
According to the Bohr model of the atom, electrons occupy specific energy levels or orbits around the nucleus. These energy levels are quantized, meaning electrons can only exist in these defined states.

3. **Electron Transition**:
When an electron transitions from a higher energy level (orbit) to a lower energy level, it releases energy. This energy can be emitted in the form of electromagnetic radiation, which includes X-rays.

4. **Identifying the Correct Option**:
- **Option A**: Electron from lower to higher - This would require energy absorption, not emission.
- **Option B**: Electron from higher to lower - This is the correct option as it involves the emission of energy in the form of X-rays.
- **Option C**: Proton from lower to higher - Protons do not jump between energy levels in the same manner as electrons.
- **Option D**: Proton from higher to lower - Again, protons do not produce X-rays through such transitions.

5. **Conclusion**:
Therefore, the correct answer is that X-rays are produced by the jumping of electrons from higher energy levels to lower energy levels.

### Final Answer:
**B**: Electrons from higher to lower energy levels.

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