Diphtheria is characterised by

Options

A. Gum bleeding
B. Suffocation
C. Hydrophobia
D. Dehydration.

Answer

### Step-by-Step Solution:

1. **Understanding Diphtheria**: Diphtheria is an infectious disease caused by the bacterium *Corynebacterium diphtheriae*. It primarily affects the respiratory system, particularly the nose and throat.

2. **Symptoms of Diphtheria**: The disease is characterized by the formation of a thick, grayish membrane in the throat. This membrane can obstruct the airway, leading to breathing difficulties.

3. **Identifying Key Characteristics**: The most significant symptom of diphtheria is the difficulty in breathing due to the obstruction caused by the membrane. This can lead to suffocation if not treated promptly.

4. **Evaluating the Options**:
- **Gum bleeding**: This is not a characteristic of diphtheria.
- **Suffocation**: This is a direct consequence of the throat obstruction caused by the diphtheria membrane.
- **Hydrophobia**: This is associated with rabies, not diphtheria.
- **Dehydration**: While dehydration can occur in various illnesses, it is not a primary characteristic of diphtheria.

5. **Conclusion**: Based on the symptoms and the effects of the disease, the correct answer is that diphtheria is characterized by **suffocation**.

### Final Answer:
Diphtheria is characterized by **suffocation**.

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