Answer;
-Mitochondria
Step-by-step explanation;
-Viruses are small infectious agents that replicates only inside the living cells of other organisms. Some of the features of viruses includes;
-They are enclosed in a protective envelope.
-They have spikes, which helps them to attach to the host cell.
-They are non cellular.
-They do not respire, do not metabolize and do not grow but they do reproduce.
-They contain a protein coat called the capsid.
-They have a nucleic acid core containing DNA or RNA.