Narcotics include

Options

A. Papaver
B. Nicotiana
C. Datura
D. Rauwolfia

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Narcotics**:
- Narcotics are drugs that alter mood and behavior. They are primarily used for their sedative and analgesic (pain-relieving) effects.

2. **Source of Narcotics**:
- Narcotics are derived from opium, which is the dried latex obtained from the unripe seed pods of the poppy plant, specifically *Papaver somniferum*.

3. **Classification**:
- Narcotics are classified as opiates, which are a type of depressant that affects the central nervous system (CNS).

4. **Effects of Narcotics**:
- They have several physiological effects, including:
- Sedation (inducing sleep)
- Analgesia (pain relief)
- Slowing down respiratory activities
- Constricting pupils
- Impairing digestion
- Causing nausea and vomiting

5. **Identifying the Correct Option**:
- Among the options provided (Papavir, Nicotiana, Dildora, Raufolia), the correct answer is *Papaver*, as it refers to the poppy plant from which opium is derived.

6. **Final Answer**:
- Therefore, narcotics include *Papaver*.

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