Virus consists of

Options

A. Protein
B. Nucleic acid
C. Protein and RNA
D. Protein and nucleic acid

Answer

**Step-by-Step Solution:**

1. **Understanding Viruses**: Begin by recognizing that viruses are ultramicroscopic entities that can only replicate inside a host cell. Outside the host, they exist in an inert state.

2. **Composition of Viruses**: Viruses are composed of two main components: nucleic acids and proteins. The nucleic acids can be either DNA or RNA, which serve as the genetic material of the virus.

3. **Nucleoprotein Particles**: Viruses are classified as nucleoprotein particles, meaning they consist of nucleic acids (DNA or RNA) that are encapsulated by a protein coat. This protein coat protects the genetic material.

4. **Options Analysis**:
- Option 1: Protein - This is incomplete as it does not include nucleic acids.
- Option 2: Nucleic Acid - This is also incomplete as it does not include proteins.
- Option 3: Protein and RNA - This is partially correct but does not account for DNA viruses.
- Option 4: Protein and Nucleic Acid - This is the most accurate as it encompasses both components.

5. **Conclusion**: The correct answer is that a virus consists of both protein and nucleic acid.

**Final Answer**: A virus consists of protein and nucleic acid.

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