A chronic disease is

Options

A. hypertension
B. typhoid
C. diarrhoea
D. kala-azar

Explanation

**Step-by-Step Solution:**

1. **Definition of Chronic Disease**: A chronic disease is defined as a health condition that lasts for one year or more. It often requires ongoing medical attention and can limit daily activities.

2. **Examples of Chronic Diseases**: Chronic diseases include conditions like hypertension, diabetes, and certain types of cancer. These diseases typically require continuous treatment and management.

3. **Analysis of Given Options**:
- **Hypertension**: This is a chronic disease as it requires lifelong management and medication.
- **Typhoid**: This is an acute disease caused by Salmonella typhi, which can be treated and resolved within a few weeks.
- **Diarrhea**: This is usually caused by infections (like E. coli) and is also an acute condition that resolves in a short time.
- **Kalaza (Kala-azar)**: This is a disease caused by the Leishmania parasite, but it is generally not classified as chronic since it can be treated effectively in a few weeks.

4. **Conclusion**: Among the options provided, hypertension is the only condition that qualifies as a chronic disease because it requires long-term treatment and management.

5. **Final Answer**: Therefore, the correct answer is hypertension.

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