Which of the following is an incorrect match between virus, genome and its mode of transmission?

Options

A. Hepatitis A virus — ss RNA — Faeco-oral route
B. Hepatitis B virus — ds RNA — Sexual contact
C. Polio virus — ss RNA — Faeco-oral route
D. Paramyxovirus — ss RNA — Saliva of infected person

Answer

To solve the question, "Which of the following is an incorrect match between virus, genome and its mode of transmission?", we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Viruses and Their Characteristics**:
- **Hepatitis A Virus**:
- Genome: Single-stranded RNA
- Mode of Transmission: Fecal-oral route
- **Hepatitis B Virus**:
- Genome: Double-stranded DNA (this is crucial)
- Mode of Transmission: Sexual contact
- **Poliovirus**:
- Genome: Single-stranded RNA
- Mode of Transmission: Fecal-oral route
- **Paramyxovirus**:
- Genome: Single-stranded RNA
- Mode of Transmission: Saliva from an infected person

2. **Evaluate Each Option**:
- **Hepatitis A Virus**: The match is correct as it is indeed a single-stranded RNA virus transmitted via the fecal-oral route.
- **Hepatitis B Virus**: This is where the error lies. It is incorrectly stated as a double-stranded RNA virus; it is actually a double-stranded DNA virus. The mode of transmission (sexual contact) is correct, but the genomic content is incorrect.
- **Poliovirus**: This is a correct match as it is a single-stranded RNA virus transmitted via the fecal-oral route.
- **Paramyxovirus**: This is also a correct match as it is a single-stranded RNA virus transmitted through saliva.

3. **Conclusion**:
- The incorrect match is with the **Hepatitis B Virus**, which is incorrectly labeled as a double-stranded RNA virus instead of a double-stranded DNA virus.

### Final Answer:
The incorrect match is **Hepatitis B virus - double-stranded RNA, sexual contact**.