This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
CD21 receptors bind to which virus - 
Select and explain. 
A. CMV, B. EBV, C. Rabies virus, D. HSV
B: EBV
Answer: B: EBV 
Explanation: Ans. is 'b' i.e., EBV * EBV belongs to Herpes virus family.* Infection is most common in early childhood, with a second peak during late adolescence.* Infectious mononucleosis (IM) is usually a disease of young adults.* EBV is transmitted by saliva (oral secretions) of infected person.* Intimate oral contact, as in kissing is the predominant mode of transmission - causes kissing disease.* The virus enter the pharyngeal epithelial cells and B cells through (CR2 / or CD21) receptors.* Memory B Cells are the reservoir of EBV.