Viruses

21. Which of the following viruses causes chickenpox?

a) Herpes simplex virus

b) Varicella-zoster virus

c) Human immunodeficiency virus (HIV)

d) Hepatitis B virus

22. The immune response mediated by antibodies is most effective against which type of viral infection?

a) Extracellular viruses

b) Intracellular viruses

c) DNA viruses

d) Retroviruses

23. The viral enzyme responsible for reverse transcription in retroviruses is called:

a) Reverse transcriptase

b) RNA polymerase

c) DNA polymerase

d) Ligase

24. Which of the following viruses is responsible for causing infectious mononucleosis?

a) Epstein-Barr virus

b) Influenza virus

c) Human immunodeficiency virus (HIV)

d) Hepatitis C virus

25. The process of a virus integrating its DNA into the host genome is characteristic of which type of virus?

a) DNA virus

b) RNA virus

c) Retrovirus

d) Papillomavirus