Bovine spongiform encephalopathy is caused by

Options

A. an agent having RNA without protein coat
B. an agent having RNA with protein coat
C. an agent consisting of abnormally folded protein.
D. an agent having iII - defined nucleus with cell wall

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about Bovine Spongiform Encephalopathy (BSE), commonly known as mad cow disease.

2. **Understand the Nature of the Disease**: BSE is a brain disorder that primarily affects adult cattle. It is characterized by the degeneration of brain tissue, leading to severe neurological symptoms.

3. **Transmission**: BSE can be transmitted to humans through the consumption of infected meat products from cattle that have the disease.

4. **Determine the Cause**: The primary cause of BSE is the presence of prions, which are misfolded proteins that induce abnormal folding of normal proteins in the brain.

5. **Analyze the Options**:
- The first option mentions "an agent having RNA without protein coat," which is incorrect because BSE is caused by proteins, not RNA.
- The second option mentions "an agent having RNA with protein coat," which is also incorrect for the same reason.
- The third option states "an agent consisting of abnormal fold-in protein," which accurately describes prions.
- The fourth option mentions "an agent having ill-defined nucleus with cell wall," which is incorrect as prions do not have a cellular structure.

6. **Conclusion**: The correct answer is that Bovine Spongiform Encephalopathy is caused by an agent consisting of abnormal fold-in protein, which refers to prions.

**Final Answer**: Bovine spongiform encephalopathy is caused by prions (abnormal fold-in proteins).

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