Name on disease of mulbery silkworm caused by a protozoan:

Options

A. Pebrine
B. Graseri
C. Flacheri
D. Muscardine

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a disease of the mulberry silkworm that is caused by a protozoan.

2. **Identifying the Protozoan**: Protozoa are single-celled organisms that can cause diseases in various hosts, including insects like the mulberry silkworm.

3. **Researching Diseases of Mulberry Silkworm**: Among the diseases that affect mulberry silkworms, we need to identify which one is caused by a protozoan.

4. **Identifying the Disease**: The disease caused by a protozoan in mulberry silkworms is known as "Pebrine".

5. **Scientific Name**: The scientific name of the protozoan responsible for Pebrine is *Nosema bombicis*.

6. **Conclusion**: Therefore, the disease of the mulberry silkworm caused by a protozoan is Pebrine.

**Final Answer**: Pebrine (caused by *Nosema bombicis*).

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