Which one of the following does not experience strong nuclear force?

Options

A. Leptons
B. Baryons
C. Hadrons
D. Proton

Answer

To determine which of the following particles does not experience the strong nuclear force, we will analyze each option provided:

1. **Leptons**: These are fundamental particles that do not experience the strong nuclear force. They include electrons, muons, and neutrinos. Leptons have a spin of 1/2 and are not subject to the strong interactions that govern the behavior of hadrons.

2. **Baryons**: These are a type of hadron, which are particles that do experience the strong nuclear force. Baryons are composed of three quarks and include protons and neutrons. They are subject to strong interactions.

3. **Hadrons**: This term encompasses both baryons and mesons, which are particles that also experience the strong nuclear force. Hadrons are made up of quarks held together by the strong force.

4. **Protons**: Protons are baryons and thus experience the strong nuclear force. They are one of the fundamental building blocks of atomic nuclei.

From this analysis, we can conclude that the particle that does not experience the strong nuclear force is **leptons**.

### Final Answer:
The correct answer is **leptons**.

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