This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
A 40 year old man underwent kidney transplantation. Two month after transplantation,
he developed fever and feature suggestive of bilateral diffuse interstitial pneumonia. Which of the following is most likely etiologic agent ? 
Select and explain. 
A. Herpes simplex virus, B. Cytomegalovirus, C. Epstein-barr virus, D. Varicella - zoster virus
B: Cytomegalovirus
Answer: B: Cytomegalovirus 
Explanation: It is a case of diffuse interstitial pneumonitis due to CMV.

Remember :

CMV is the MC infection complicating organ transplantation.
CMV is MC cause of intrauterine infection.
Risk of post transplant CMV infection is greatest 5-13 weeks after transplant.

Infections after Kidney Transplantation