Common cold, the most contagious disease is due to

Options

A. rhino and adeno viruses
B. rubella virus
C. varicella virus
D. SV 40 virus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which virus is responsible for causing the common cold, which is known to be highly contagious.

2. **Identifying the Options**: The options provided are:
- a) Rhino and adenoviruses
- b) Rubella virus
- c) Varicella virus
- d) SV40 virus

3. **Analyzing the Common Cold**: The common cold is primarily caused by viral infections. It is transmitted through airborne droplets from an infected person or through direct contact with infected secretions, such as from a runny nose.

4. **Reviewing the Viruses**:
- **Rhino and Adenoviruses**: These are known to be the primary causes of the common cold.
- **Rubella Virus**: This virus causes German measles, not the common cold.
- **Varicella Virus**: This virus is responsible for chickenpox.
- **SV40 Virus**: This virus is associated with certain types of cancer, including brain and bone cancers.

5. **Selecting the Correct Answer**: Based on the analysis, the correct answer is option **a) Rhino and adenoviruses**, as they are the viruses most commonly associated with the common cold.

**Final Answer**: The common cold, the most contagious disease, is due to **a) Rhino and adenoviruses**.

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