Nosema bombycis which causes pebrine in silk worms is a

Options

A. Fungus
B. Virus
C. Bacterium
D. Protozoan

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about "Nosema bombycis," which is known to cause a disease called pebrine in silkworms.

2. **Understand the Disease**: Pebrine is a disease that affects silkworms, specifically the larvae, leading to significant impacts on silk production.

3. **Classify the Organism**: To determine what type of organism "Nosema bombycis" is, we need to look at the options provided: fungus, virus, bacterium, or protozoan.

4. **Research the Characteristics**: Nosema bombycis is known to be a protozoan parasite. Protozoans are single-celled organisms that can cause diseases in various hosts, including insects like silkworms.

5. **Conclude the Answer**: Since Nosema bombycis is classified as a protozoan parasite, the correct answer to the question is that it is a protozoan.

6. **Final Answer**: Therefore, the answer to the question is: "Nosema bombycis, which causes pebrine in silkworms, is a protozoan."

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