Which of these sets of sub-atomic particles make up the nucleus of an atom?

Options

A. Protons and neutrons
B. Protons and electrons
C. Electrons and neutrons
D. Electrons, protons and neutrons

Answer

To determine which set of sub-atomic particles make up the nucleus of an atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of an Atom**:
- An atom consists of a nucleus at its center and electrons that orbit around the nucleus.

2. **Identify the Components of the Nucleus**:
- The nucleus is made up of two types of sub-atomic particles: protons and neutrons.

3. **Define Protons and Neutrons**:
- Protons are positively charged particles found in the nucleus.
- Neutrons are neutral particles (they have no charge) also located in the nucleus.

4. **Determine the Charge of the Nucleus**:
- Since the nucleus contains protons (which are positively charged) and neutrons (which are neutral), the overall charge of the nucleus is positive.

5. **Evaluate the Options Given**:
- If the options provided include protons and neutrons together, that set represents the nucleus of an atom.

6. **Select the Correct Answer**:
- Based on the understanding that the nucleus is composed of protons and neutrons, the correct option would be the one that lists both protons and neutrons.

### Conclusion:
The correct answer is the option that includes both **protons and neutrons** as they are the particles that make up the nucleus of an atom.

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