Rutherford's experiment led to the discovery of

Options

A. Nucleus
B. Electron
C. Proton
D. `alpha`-particle

Answer

### Step-by-Step Solution:

1. **Understanding Rutherford's Experiment**:
- Rutherford conducted an experiment where he bombarded a thin foil of gold with alpha particles. Alpha particles are positively charged particles emitted from radioactive materials.

2. **Observation of Alpha Particles**:
- In the experiment, most of the alpha particles passed straight through the gold foil without any deflection. This observation suggested that the majority of the atom is empty space.

3. **Scattering of Alpha Particles**:
- A small number of alpha particles were deflected at small angles, and a very few were deflected back at angles close to 180 degrees. This indicated that there was a concentrated mass within the atom.

4. **Conclusion Drawn**:
- From these observations, Rutherford concluded that there must be a dense center within the atom that contains most of the atom's mass. This center was later termed the "nucleus."

5. **Significance of the Discovery**:
- The discovery of the nucleus was pivotal as it led to the understanding of atomic structure, showing that atoms consist of a small, dense nucleus surrounded by electrons.

### Final Answer:
Rutherford's experiment led to the discovery of the **nucleus**.

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