Which is an infectious disease -

Options

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

Answer

To determine which of the given options is an infectious disease, we need to analyze each option based on the definition of infectious diseases.

**Step 1: Understand the definition of infectious diseases.**
Infectious diseases are caused by microorganisms such as bacteria, viruses, fungi, or parasites. They can be transmitted from one individual to another.

**Step 2: Analyze the options provided.**
- **Coronary Thrombosis:** This condition is related to the formation of a blood clot in the coronary arteries, leading to a heart attack. It is not caused by an infectious agent; rather, it is a cardiovascular condition.

- **Diphtheria:** This is an infectious disease caused by the bacterium *Corynebacterium diphtheriae*. It primarily affects the mucous membranes of the throat and upper respiratory tract. It is transmitted from person to person.

- **Diabetes Mellitus:** This is a metabolic disorder characterized by high blood sugar levels due to insufficient insulin production or insulin resistance. It is not caused by an infectious agent.

- **Hypertension:** Also known as high blood pressure, this condition is related to the force of blood against the arterial walls. It is not caused by an infectious agent.

**Step 3: Identify the infectious disease.**
From the analysis, it is clear that the only infectious disease among the options is **diphtheria**, as it is caused by a bacterium and can be transmitted between individuals.

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

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