Which of the following statements is true about viruses?

• A. Viruses require a host cell to reproduce.
• B. Viruses can generate energy through cellular respiration.
• C. Viruses contain both DNA and RNA in all cases.
• D. Viruses are classified as prokaryotic organisms.

Answer: (A)

Verified step by step guidance

1. Understand the nature of viruses: Viruses are unique infectious agents that cannot carry out metabolic processes on their own and must rely on a host cell for reproduction.
2. Evaluate the statement 'Viruses require a host cell to reproduce': This is true because viruses lack the cellular machinery needed for independent replication and must hijack a host's cellular mechanisms.
3. Consider the statement 'Viruses can generate energy through cellular respiration': This is false because viruses do not have the organelles or enzymes necessary for cellular respiration or energy production.
4. Analyze the statement 'Viruses contain both DNA and RNA in all cases': This is incorrect since viruses contain either DNA or RNA as their genetic material, but never both simultaneously.
5. Review the statement 'Viruses are classified as prokaryotic organisms': This is false because viruses are not classified as living cells and do not fit into the prokaryotic or eukaryotic domains; they are considered acellular entities.