Which is a an infectious disease

Options

A. Coronary thrombosis
B. Diphtheria
C. Diabetes mellitus
D. Hypertension

Answer

**Step-by-Step Solution:**

1. **Understanding Infectious Diseases**: An infectious disease is caused by the entry of pathogens (such as bacteria, viruses, fungi, or parasites) into the body, leading to illness.

2. **Analyzing the Options**: We need to evaluate each option provided to determine which one is caused by an infectious agent.

3. **Option 1 - Coronary Thrombosis**: This condition involves the formation of a blood clot in a coronary artery. It is related to physiological changes in the body and is not caused by an infectious agent. Therefore, this is not an infectious disease.

4. **Option 2 - Diphtheria**: This is a bacterial infection caused by the bacterium *Corynebacterium diphtheriae*. It is transmitted through droplet infection when an infected person coughs or sneezes. Since it is caused by a pathogen, this qualifies as an infectious disease.

5. **Option 3 - Diabetes Mellitus**: This is a metabolic disorder characterized by high blood sugar levels due to insulin dysfunction. It is not caused by an infectious agent, so it is not an infectious disease.

6. **Option 4 - Hypertension**: Hypertension, or high blood pressure, is a condition that arises from various physiological factors and is not caused by an infection. Thus, it is not an infectious disease.

7. **Conclusion**: After analyzing all the options, the only disease that is infectious is Diphtheria.

**Final Answer**: Diphtheria is an infectious disease.

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