Orange rot is caused by

Options

A. Bacterium
B. fungus
C. Citrus
D. Mycoplasma

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the cause of "orange rot," which is a disease affecting citrus plants.

2. **Consider the Options**: The options provided are:
- Bacterium
- Fungus
- Citrus
- Mycoplasma

3. **Analyze Each Option**:
- **Bacterium**: While some diseases are caused by bacteria, orange rot is not one of them.
- **Fungus**: This is a strong candidate as fungal infections are common in plants. Specifically, orange rot is known to be caused by a fungus.
- **Citrus**: This is not a pathogen; it refers to the type of plant affected by the disease.
- **Mycoplasma**: These are small, bacteria-like organisms, but they do not cause orange rot.

4. **Identify the Causative Agent**: The specific fungus responsible for orange rot is identified as *Alternaria citri*, which belongs to the group of fungi known as Ascomycetes.

5. **Conclusion**: Based on the analysis, the correct answer to the question "Orange rot is caused by" is **fungus**.

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