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 ssDNA virus
D. A dsRNA virus

Answer

To solve the question regarding retroviruses, we will analyze each option provided and determine which one correctly describes the characteristics of retroviruses.

### Step-by-Step Solution:

1. **Understanding Retroviruses:**
- Retroviruses are a type of virus that primarily contain RNA as their genetic material. The defining feature of retroviruses is their ability to reverse the usual flow of genetic information.

2. **Analyzing the Options:**
- **Option 1:** "A RNA virus that can synthesize DNA during the infection."
- This statement is true. Retroviruses use an enzyme called reverse transcriptase to convert their RNA into DNA once they infect a host cell.

- **Option 2:** "A DNA virus that can synthesize RNA during infection."
- This statement is incorrect. Retroviruses are not DNA viruses; they are RNA viruses.

- **Option 3:** "A single standard DNA virus."
- This statement is also incorrect. Retroviruses are not DNA viruses; they are single-stranded RNA viruses.

- **Option 4:** "A double standard RNA virus."
- This statement is incorrect as well. Retroviruses are single-stranded RNA viruses, not double-stranded.

3. **Conclusion:**
- Based on the analysis, the correct option regarding retroviruses is **Option 1: "A RNA virus that can synthesize DNA during the infection."**

### Final Answer:
- The correct option is **Option 1**.