A solar eclipse that occurs when the moon's umbra reaches Earth's surface is! called:

Options

A. a total solar eclipse
B. a partial solar eclipse
C. an annular solar eclipse
D. a penumbral solar eclipse

Explanation

**Step-by-Step Solution:**

1. **Understanding Solar Eclipses**: A solar eclipse occurs when the Moon passes between the Earth and the Sun, blocking the Sun's light partially or completely.

2. **Identifying the Umbra**: The umbra is the darkest part of the Moon's shadow, where the sunlight is completely blocked.

3. **Condition for Total Solar Eclipse**: A total solar eclipse occurs when the Moon's umbra reaches the Earth's surface. This means that the area on Earth directly under the umbra will experience complete darkness during the day.

4. **Options Analysis**: The question provides four options:
- A) Total Solar Eclipse
- B) Partial Solar Eclipse
- C) Annular Solar Eclipse
- D) Penumbral Solar Eclipse

5. **Determining the Correct Answer**: Since the question specifies that the Moon's umbra reaches the Earth's surface, the correct answer is:
- **A) Total Solar Eclipse**.

6. **Conclusion**: Therefore, a solar eclipse that occurs when the Moon's umbra reaches the Earth's surface is called a **Total Solar Eclipse**.

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