Quantam theory of radiation was proposed by

Options

A. Pauli
B. Planck
C. Hund
D. Aufbau

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who proposed the quantum theory of radiation. This is a historical question related to the development of quantum mechanics.

2. **Identifying the Options**: The options provided are Pauli, Planck, Hund, and Abbaub. We need to determine which of these scientists is associated with the quantum theory of radiation.

3. **Researching Each Scientist**:
- **Pauli**: Known for the Pauli Exclusion Principle, which states that no two electrons can have the same set of quantum numbers in an atom.
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