Viruses possess :

Options

A. DNA only
B. Nucleic acid, DNA or RNA
C. Protein only
D. Nucleic acid and protein

Answer

### Step-by-Step Solution:

1. **Understanding Viruses**:
- Viruses are infectious agents that can cause diseases in living organisms. They are not classified as living organisms because they cannot reproduce on their own and require a host cell to replicate.

2. **Genetic Material in Viruses**:
- Viruses contain genetic material, which can be either DNA (Deoxyribonucleic Acid) or RNA (Ribonucleic Acid). This genetic material is essential for the virus to replicate and produce new virus particles.

3. **Structure of Viral Genetic Material**:
- The genetic material in viruses can be either single-stranded or double-stranded.
- For DNA viruses, the DNA can be double-stranded or single-stranded.
- For RNA viruses, the RNA can also be double-stranded or single-stranded.

4. **Protein Coat**:
- The genetic material of a virus is protected by a protein coat known as the capsid. This capsid is crucial for the virus's ability to infect host cells and helps in the protection of the genetic material.

5. **Common Types of Viral Genetic Material**:
- In most animal viruses, the genetic material is DNA, while in most plant viruses, it is RNA.

6. **Conclusion**:
- Therefore, viruses possess both nucleic acids (either DNA or RNA) and proteins (in the form of a capsid). The correct answer to the question is that viruses possess nucleic acids and proteins.

### Final Answer:
Viruses possess nucleic acids (DNA or RNA) and proteins (capsid).

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