Polio' is caused by

Options

A. Virus with double-standed DNA
B. Virus with double-standed RNA
C. Virus with single-standed DNA
D. Virus with single-standed RNA

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the causative agent of polio, also known as poliomyelitis.

2. **Understand the Nature of Viruses**: Viruses can have different types of genetic material, which can be either DNA or RNA. Additionally, this genetic material can be single-stranded or double-stranded.

3. **Analyze the Options**: The options provided are:
- A virus with double-stranded DNA
- A virus with double-stranded RNA
- A virus with single-stranded DNA
- A virus with single-stranded RNA

4. **Recall Information about Poliovirus**: Polio is specifically caused by a virus. To determine which type of virus causes polio, we need to know the characteristics of the poliovirus.

5. **Identify the Correct Type of Virus**: The poliovirus is known to be a virus that contains single-stranded RNA as its genetic material.

6. **Conclude the Answer**: Therefore, the correct answer to the question "Polio is caused by" is a virus with single-stranded RNA.

**Final Answer**: Polio is caused by a virus with single-stranded RNA.

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