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: Unknown
One virus particles prevents multiplication of 2nd virus. This phenomena is: 
Select and explain. 
A. Viral interference, B. Mutation, C. Supervision, D. Permutation
A: Viral interference
Answer: A: Viral interference 
Explanation: Viral interference
Interference in which infectionof a cell by one virus inhibits simultaneous or subsequent infection by another virus.
Most important mediator of interference is interferon.
Interference produced by destruction of cell receptors is seen with myxoviruses and enterovirus.
It is applied in the field in controlling poliomyelitis outbreaks by in controlling poliomyelitis outbreaks by introducing into the population, the live attenuated poliovirus vaccine.