question: Q:An investigator is studying the effect that mutations in different parts of the respiratory tract have on susceptibility to infection. A mutation in the gene encoding for the CD21 protein is induced in a sample of cells obtained from the nasopharyngeal epithelium. This mutation is most likely to prevent infection with which of the following viruses?? 
  {'A': 'Rhinovirus', 'B': 'Epstein-Barr virus', 'C': 'Human immunodeficiency virus', 'D': 'Cytomegalovirus', 'E': 'Parvovirus'},