A medicine, extracted from the bark of a plant, is used in the treatment of malaria. Identify the medicine.

Options

A. Quinine
B. Tetracycline
C. Penicillin
D. Sulfadiazine

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a medicine that is extracted from the bark of a plant and is used to treat malaria.

2. **Identifying the Disease**: Malaria is caused by a parasite known as Plasmodium falciparum, which infects red blood cells in the human body. It is important to recognize the seriousness of malaria as it can be fatal.

3. **Recognizing Treatment Options**: To treat malaria, anti-malarial compounds are required. These compounds are specifically designed to combat the malaria-causing parasites.

4. **Identifying the Source of the Medicine**: The question specifies that the medicine is derived from the bark of a plant. This hints at traditional or herbal medicines that have been used historically.

5. **Identifying the Correct Medicine**: The medicine that fits the description of being extracted from the bark of a plant and used for treating malaria is quinine. Quinine is well-known for its effectiveness against malaria.

6. **Understanding the Mechanism of Action**: Quinine works by killing the malaria parasites and preventing their growth in the body, thus helping to cure or prevent malaria.

7. **Final Answer**: Therefore, the medicine extracted from the bark of a plant that is used in the treatment of malaria is **Quinine**.

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