Which of the following types of viruses are known to infect all vertebrate species?

• A. Herpesviruses and adenoviruses
• B. None; no single virus type infects all vertebrates
• C. Retroviruses and orthomyxoviruses
• D. Rhabdoviruses and paramyxoviruses

Answer: (B)

Verified step by step guidance

1. Understand the question: It asks which virus types infect all vertebrate species, meaning the virus must have a host range that includes every vertebrate group (fish, amphibians, reptiles, birds, mammals).
2. Recall the host range characteristics of each virus family: Herpesviruses and adenoviruses typically infect specific vertebrate groups but not all; retroviruses and orthomyxoviruses also have limited host ranges; rhabdoviruses and paramyxoviruses infect various vertebrates but not universally all.
3. Consider the biological diversity of vertebrates and the specificity of virus-host interactions, which usually restrict viruses to certain species or groups rather than all vertebrates.
4. Conclude that no single virus type is known to infect all vertebrate species because of these host range limitations and evolutionary adaptations.
5. Therefore, the correct understanding is that none of the listed virus types infect all vertebrates, which aligns with the answer stating 'None; no single virus type infects all vertebrates.'