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

To solve the question of selecting the correct statement from the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- **Statement:** Morphine is often given to a person who has undergone surgery as a painkiller.
- **Evaluation:** This statement is correct. Morphine is an opioid pain medication commonly used to manage severe pain post-surgery.

2. **Analyze the Second Statement:**
- **Statement:** Chewing tobacco lowers blood pressure and heart rate.
- **Evaluation:** This statement is incorrect. The nicotine in tobacco actually increases blood pressure and heart rate, not lowers them.

3. **Analyze the Third Statement:**
- **Statement:** Cocaine is given to patients after surgery as it stimulates recovery.
- **Evaluation:** This statement is incorrect. Cocaine is used as a local anesthetic before surgery, not after, and it does not stimulate recovery.

4. **Analyze the Fourth Statement:**
- **Statement:** Barbiturates when given to criminals make them tell the truth.
- **Evaluation:** This statement is incorrect. While barbiturates are sedatives used for anxiety and insomnia, the drug commonly referred to as a "truth serum" is sodium thiopental, not barbiturates.

5. **Conclusion:**
- After evaluating all the statements, the only correct statement is: **Morphine is often given to a person who has undergone surgery as a painkiller.**

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

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