Choose the correct option regarding Retrovirus

Options

A. an RNA virus that can synthesise DNA during infection.
B. a DNA virus that can synthesise RNA during infection.
C. a ss DNA virus.
D. a dsRNA virus.

Explanation

**Step-by-Step Solution:**

1. **Identify the Type of Virus**: Retroviruses are classified as RNA viruses. This means their genetic material is composed of RNA.

2. **Understand the Replication Process**: When a retrovirus infects a host cell, it uses an enzyme called reverse transcriptase to convert its RNA into DNA. This is a key characteristic of retroviruses.

3. **Integration into Host Genome**: After the retrovirus converts its RNA into DNA, the newly formed viral DNA enters the nucleus of the host cell. Here, it integrates into the host's genome, allowing it to replicate along with the host's DNA.

4. **Evaluate the Given Options**:
- **Option A**: "It is an RNA virus that can synthesize DNA during infection." - This is correct as it accurately describes the retrovirus.
- **Option B**: "It is a DNA virus that can synthesize RNA during infection." - This is incorrect since retroviruses are RNA viruses, not DNA viruses.
- **Option C**: "It is a single-stranded DNA virus." - This is incorrect; retroviruses are RNA viruses, not DNA viruses.
- **Option D**: "It is a double-stranded RNA virus." - This is also incorrect; retroviruses are single-stranded RNA viruses.

5. **Conclusion**: Based on the evaluation of the options, the correct answer is **Option A**.