Which is the series of satellites used by India for astronomical observation?

Options

A. Agni
B. Rohini
C. INSAT
D. Vijay

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the series of satellites used by India specifically for astronomical observations.

2. **Identifying the Options**: The options provided are:
- Option 1: Agni
- Option 2: Rohini
- Option 3: Insat
- Option 4: Vijay

3. **Analyzing Each Option**:
- **Agni**: This is primarily known as a series of ballistic missiles and not for astronomical observations.
- **Rohini**: This series of satellites was specifically launched for Earth observation and astronomical purposes. It was developed by the Indian Space Research Organization (ISRO).
- **Insat**: This series is mainly used for telecommunications, broadcasting, meteorology, and search and rescue operations, not specifically for astronomical observations.
- **Vijay**: This option does not correspond to any recognized series of satellites used for astronomical purposes.

4. **Conclusion**: The series of satellites used by India for astronomical observations is the **Rohini** series.

5. **Final Answer**: The correct answer is **Option 2: Rohini**.

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