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
Which pox virus won't grow in egg, animal cells - 
Select and explain. 
A. Cow pox, B. Vaccinia, C. Variola, D. Molluscum
D: Molluscum
Answer: D: Molluscum 
Explanation: Humans are the only susceptible hosts for molluscum contagiosum virus. The virus cannot be grown in eggs, tissue cultures or animals.
Vaccinia virus may be grown in a wide range of animals.
Variola can be grown in the monkey.
Cowpox virus, as the name suggests, infects cow; and also humans.