Kerosene is used in/as:

Options

A. jet engines
B. fuel
C. ointments
D. lubricants

Explanation

**Step-by-Step Solution:**

1. **Understanding Kerosene**: Kerosene is a flammable hydrocarbon liquid derived from petroleum. It is commonly used as a fuel.

2. **Identifying Uses of Kerosene**: Kerosene has various applications. Some of the common uses include:
- As a fuel for heating and cooking.
- In lamps for lighting.
- As a fuel for jet engines.
- As a solvent in various industrial processes.

3. **Focusing on Jet Engines**: Among the various uses, one of the most significant applications of kerosene is in aviation. Jet engines, which power aircraft, often use kerosene-based fuels due to their high energy content and efficiency at high altitudes.

4. **Conclusion**: Based on the information gathered, the primary use of kerosene in the context of the question is as a fuel for jet engines.

**Final Answer**: Kerosene is used in jet engines.

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