The earliest use of petroleum was in

Options

A. Heating
B. Furnace
C. Medicine
D. Production of gas

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
- The question asks about the earliest use of petroleum among the given options: heating, furnace, medicine, or production of gas.

2. **Analyzing the Options:**
- **Heating:** While petroleum is used for heating today, it may not be the earliest use.
- **Furnace:** Similar to heating, this is a modern application of petroleum.
- **Medicine:** Historical accounts suggest that petroleum was used for medicinal purposes in ancient times.
- **Production of Gas:** This is a more recent development and not an early use.

3. **Historical Context:**
- Research indicates that petroleum was used by ancient civilizations. Desert nomads reportedly used it to treat their camels.
- Additionally, some Roman emperors are believed to have used petroleum to alleviate gout.

4. **Conclusion:**
- Based on the historical evidence and analysis, the earliest use of petroleum is identified as a medicinal purpose.

5. **Final Answer:**
- The correct answer is **C. Medicine.**

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