Virus are living because they:
Reproduce, have Genetic Material (Nucleic Acids) and Adapt
.
Explanation:
Virus have genes or genetic material which are layered in a capsid or protein coat and sometimes a lipid bilayer.
It is not made up of cells yet can be considered a living organism because of the genetic material RNA or DNA in it.
The infect the host and take over host replication machinery and replicates itself. Although it is not able to replicate outside the living body.
They adapt to the host's body environment as many adaptation are present in it as capsid layer which protects its genetic material from getting degrade till the time it reaches nucleus of the cell.
There are 7 point criteria for an organism to be living, virus fulfils some of it except having made up of cells and having cellular organization.