The instrument which is used to identify the geographical directions is

Options

A. manometer
B. barometer
C. periscope
D. magnetic comapss

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the instrument that is used to identify geographical directions. This means we need to find a tool that helps us determine where north, south, east, and west are located.

2. **Analyzing the Options**: The options provided are:
- Option 1: Manometer
- Option 2: Barometer
- Option 3: Pre-scope
- Option 4: Magnetic Compass

3. **Identifying Each Instrument**:
- **Manometer**: This is used to measure the pressure of gases or liquids, not for finding directions.
- **Barometer**: This instrument measures atmospheric pressure, which is also not related to geographical directions.
- **Pre-scope**: This term is not commonly recognized in the context of geographical instruments.
- **Magnetic Compass**: This instrument contains a magnetic needle that aligns itself with the Earth's magnetic field, pointing towards the magnetic north.

4. **Understanding the Function of a Magnetic Compass**: The magnetic compass has a magnetic needle that, when allowed to move freely, will align itself with the Earth's magnetic field. The north pole of the needle points towards the magnetic north, allowing users to identify the cardinal directions.

5. **Conclusion**: Based on the analysis, the correct answer is the **Magnetic Compass**, as it is specifically designed to identify geographical directions.

**Final Answer**: The instrument which is used to identify the geographical directions is the **Magnetic Compass** (Option 4).

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