Severity of disease symptoms depends upon

Options

A. number of microbes
B. target organ
C. both of these
D. none of these

Explanation

### Step-by-Step Solution:

1. **Understanding Severity of Disease Symptoms**:
- The severity of disease symptoms refers to how intense or serious the symptoms of a disease are. This can include the number of symptoms present, their intensity, and the duration for which they last.

2. **Role of Microbes**:
- Microbes, specifically pathogens like bacteria, viruses, and fungi, are responsible for causing diseases. The number of these microbes in the body plays a crucial role in determining the severity of the symptoms.
- If the number of microbes is low, the symptoms will generally be milder. Conversely, as the number of microbes increases, the symptoms tend to become more severe.

3. **Target Organ**:
- The specific organ or system that the microbes target also influences the severity of the symptoms. Different organs may react differently to the same pathogen, leading to variations in symptom severity.
- For example, an infection in the lungs may present more severe symptoms compared to a skin infection, even if the same type of microbe is involved.

4. **Conclusion**:
- Therefore, the severity of disease symptoms depends on both the number of microbes present and the target organ affected by the infection. Thus, the correct answer to the question is that the severity of disease symptoms depends on "both of these."

### Final Answer:
The severity of disease symptoms depends on both the number of microbes and the target organ affected by the infection.

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