Which of the following is an opioid drug?

Options

A. Heroin
B. Cocaine
C. Marijuana
D. Hashish

Explanation

**Step-by-Step Solution:**

1. **Understand the Question**: We need to identify which of the given options is an opioid drug.

2. **Define Opioid Drugs**: Opioid drugs are substances that are derived from the opium poppy plant. They primarily act on the opioid receptors in the brain and are commonly used as painkillers.

3. **Analyze the Options**:
- **Option A: Heroin** - This is derived from the opium poppy and is classified as an opioid.
- **Option B: Cocaine** - This is derived from the coca plant and is not an opioid.
- **Option C: Marijuana** - This is derived from the cannabis sativa plant and is also not an opioid.
- **Option D: Hashish** - This is also derived from the cannabis plant and is not an opioid.

4. **Identify the Correct Answer**: Among the options, heroin is the only drug that is classified as an opioid.

5. **Conclusion**: The answer to the question "Which of the following is an opioid drug?" is **Heroin**.

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