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
In a patient with a vesicle on shin. Microscopy on Tzank smear showed giant cells. Causative agents is: 
Select and explain. 
A. Vaccinia virus, B. Varicella zoster, C. Tuberculous, D. Molluscum contagiosum
B: Varicella zoster
Answer: B: Varicella zoster 
Explanation: Ans. (b) Le Varicella zoster Multinucleated giant cells and type a intranculear inclusion bodies may be seen in smears prepared by scraping the base of early vesicles (Tzank smears) and stained with toludine blue, Giemsa or Papanicolou stain" Note: Electron microscopy of vesicle fluid can demonstrate the typical virus