Which comet is visible from Earth?

Options

A. Comet Borrelly
B. Comet Encke
C. Caesar's comet
D. Halley's comet

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which comet is visible from Earth. This means we need to identify a comet that can be observed from our planet.

2. **Identifying Comets**: There are many comets that have been observed from Earth. However, some comets are more notable due to their visibility and periodic returns.

3. **Researching Notable Comets**: One of the most famous comets is Halley's Comet, which is known for its periodic appearances.

4. **Halley's Comet Details**:
- Discovered by Edmond Halley in 1758.
- It has an orbital period of approximately 75 years.
- Halley's Comet last appeared in 1986 and is expected to return in 2061.

5. **Conclusion**: Based on the information gathered, the comet that is visible from Earth is Halley's Comet.

**Final Answer**: Halley's Comet (Option 4).

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