st. Anthory's fire disease is caused by

Options

A. Bacteria
B. Fungus
C. Nematode
D. Polychaete

Explanation

**Step-by-Step Solution:**

1. **Understanding the Disease**: St. Anthony's fire is another name for ergotism, a condition that arises from the consumption of contaminated food.

2. **Identifying the Cause**: The primary cause of St. Anthony's fire (ergotism) is long-term ergot poisoning. This poisoning occurs when individuals consume food products made from grains that are infected.

3. **Source of Contamination**: The specific grain involved is rye. When rye is contaminated with a particular fungus, it leads to the production of toxic compounds.

4. **Identifying the Fungus**: The fungus responsible for this contamination is called Claviceps purpurea. This fungus infects the rye plant and produces ergot alkaloids, which are toxic.

5. **Consumption of Contaminated Food**: When people consume rye bread made from contaminated rye, they ingest these toxins, leading to the symptoms associated with ergotism, including severe skin inflammation and gangrene.

6. **Conclusion**: Therefore, the correct answer to the question "St. Anthony's fire disease is caused by" is fungus, specifically Claviceps purpurea.

**Final Answer**: St. Anthony's fire disease is caused by a fungus (Claviceps purpurea).

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