Which of the following contributes to the high level of variability in the influenza virus?

• A. Formation of endospores
• B. Conjugation
• C. Binary fission
• D. Antigenic shift and antigenic drift

Answer: (D)

Verified step by step guidance

1. Understand that the question asks about the factors contributing to the high variability of the influenza virus, which is an RNA virus known for frequent changes in its surface proteins.
2. Recall that formation of endospores is a survival mechanism used by some bacteria, not viruses, so it does not contribute to influenza variability.
3. Recognize that conjugation is a form of genetic exchange in bacteria, not applicable to viruses like influenza.
4. Binary fission is a method of asexual reproduction in bacteria and some single-celled organisms, but viruses replicate differently and do not use binary fission.
5. Focus on antigenic shift and antigenic drift, which are processes specific to influenza virus: antigenic drift involves small mutations over time, while antigenic shift involves reassortment of gene segments, both leading to high variability in viral surface proteins.