Which one of the following is not a derivative of opium?

Options

A. Cocaine
B. Heroin
C. Morphine
D. Codein

Explanation

To determine which option is not a derivative of opium, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Opium**: Opium is a narcotic drug derived from the dried latex of the opium poppy plant, scientifically known as Papaver somniferum.

2. **Identify Derivatives of Opium**: Common derivatives of opium include:
- **Morphine**: A potent pain reliever derived directly from opium.
- **Codeine**: Another pain reliever that is also derived from opium.
- **Heroin**: A semi-synthetic derivative of morphine, also derived from opium.

3. **Examine the Options**: The question asks which of the given options is not a derivative of opium.
- **Cocaine**: This is a narcotic drug but is derived from the coca plant (Erythroxylum coca), not from opium.

4. **Conclusion**: Since cocaine is obtained from a different plant and is not a derivative of opium, it is the correct answer to the question.

### Final Answer:
The option that is not a derivative of opium is **Cocaine**.

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