Answer: The correct answer is- Inside of cell.
Viruses are non living, noncellular genetic elements that require a living organism as a host to replicate. They are also known as obligate intracellular parasites.
They use the replication machinery of host in order to make more viral copies. They can replicate through two mechanisms that is Lysogenic ( where they integrate the the genome into host genome) and lytic cycle ( in which they perform the lyses of the host cell).
Example- Bacteriophage ( a virus that infects bacteria).