COVID-19 infected patients will experience mild to moderate respiratory illness due to ________.

Options

A. corona virus
B. protozoa
C. bacteria
D. fungi

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the cause of mild to moderate respiratory illness in COVID-19 infected patients.

2. **Identifying the Options**: The options provided are:
- A) Coronavirus
- B) Protozoa
- C) Bacteria
- D) Fungi

3. **Analyzing the Options**:
- **A) Coronavirus**: COVID-19 is known to be caused by a virus, specifically a type of virus called coronavirus.
- **B) Protozoa**: Protozoa are single-celled organisms that can cause diseases like malaria, but they are not responsible for COVID-19.
- **C) Bacteria**: Bacteria can cause various diseases, but COVID-19 is not caused by bacteria.
- **D) Fungi**: Fungi can cause infections, but they are not related to COVID-19.

4. **Conclusion**: Since COVID-19 is caused by a virus known as coronavirus, the correct answer is **A) Coronavirus**.

5. **Final Answer**: COVID-19 infected patients will experience mild to moderate respiratory illness due to **coronavirus**.

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