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
Smallest Virus is ? 
Select and explain. 
A. Herpes virus, B. Adenovirus, C. Parvovirus, D. Poxvirus
C: Parvovirus
Answer: C: Parvovirus 
Explanation: Ans. is `c' i.e. Parvovirus