Virus consists of

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Components of a Virus:**
A virus is a simple infectious agent that consists of two main components: nucleic acid and protein. The nucleic acid can be either DNA or RNA, while the protein forms a protective coat around the nucleic acid.

2. **Analyze the Options Given:**
- Option 1: Protein
- Option 2: Nucleic acid
- Option 3: Protein and RNA
- Option 4: Protein and nucleic acid

3. **Evaluate Each Option:**
- **Option 1 (Protein):** While protein is a component of viruses, it does not provide a complete picture since nucleic acid is also essential.
- **Option 2 (Nucleic acid):** Similar to option 1, this option is incomplete as it does not mention the protein coat.
- **Option 3 (Protein and RNA):** This option is too specific because not all viruses contain RNA; some contain DNA.
- **Option 4 (Protein and nucleic acid):** This option correctly identifies both essential components of all viruses, regardless of whether they contain RNA or DNA.

4. **Conclusion:**
Based on the analysis, the most accurate answer is Option 4, which states that a virus consists of protein and nucleic acid.

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

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