Select the correct statement from the ones given below .

Options

A. Morphine is often given to a person who have undergone surgery as a pain killer.
B. Chewing tobacco lowers blood pressure and heart rate.
C. Cocaine is given to patients after surgery as it stimulates recovery.
D. Barbiturates when given to criminals' makes them tell the truth.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to select the correct statement from a list of options regarding various substances and their effects on the human body.

2. **Analyzing Each Statement**:
- **Statement 1**: "Morphine is often given to a person who has undergone surgery as a painkiller."
- **Analysis**: Morphine is indeed an opioid and is widely used as an analgesic (pain reliever) for patients post-surgery. This statement is correct.

- **Statement 2**: "Chewing tobacco lowers blood pressure and heart rate."
- **Analysis**: Chewing tobacco actually increases blood pressure and heart rate due to the nicotine content. This statement is incorrect.

- **Statement 3**: "Cocaine is given to the patient after surgery as it stimulates recovery."
- **Analysis**: Cocaine is a stimulant and is not used after surgery due to its potential for addiction and adverse effects. This statement is incorrect.

- **Statement 4**: "Barbiturates, when given to criminals, make them tell the truth."
- **Analysis**: Barbiturates are sedatives that depress the central nervous system, but they do not guarantee truth-telling. This statement is misleading and incorrect.

3. **Conclusion**: After analyzing all the statements, the only correct statement is the first one about morphine being used as a painkiller after surgery.

4. **Final Answer**: The correct statement is: "Morphine is often given to a person who has undergone surgery as a painkiller."

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