The fundamental particle not present in nucleus is

Options

A. electron
B. proton
C. neutron
D. None of these

Answer

To solve the question "The fundamental particle not present in nucleus is", we can follow these steps:

### Step 1: Understand the Structure of an Atom
An atom consists of a nucleus at its center, which contains protons and neutrons. Electrons revolve around the nucleus in specific orbits.

### Step 2: Identify the Particles
- **Protons**: Positively charged particles found in the nucleus.
- **Neutrons**: Neutral particles also found in the nucleus.
- **Electrons**: Negatively charged particles that orbit around the nucleus.

### Step 3: Analyze the Options
The question provides four options:
- Option A: Electron
- Option B: Proton
- Option C: Neutron
- Option D: None of these

### Step 4: Determine Which Particle is Not in the Nucleus
From our understanding:
- Protons and neutrons are present in the nucleus.
- Electrons are not present in the nucleus; they exist in the space surrounding the nucleus.

### Step 5: Conclusion
Based on the analysis, the fundamental particle that is not present in the nucleus is **Option A: Electron**.

### Final Answer:
The fundamental particle not present in the nucleus is **Electron**.

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