Answer:
HDV
Explanation:
Hepatitis D virus (HDV) is classified as a virusoid as it needs a helper virus to infect the host cells. The Hepatitis D virusoid can infect the host organisms who are already infected with another Hepatitis virus (HBV) which in turn serves as a helper virus for them. The Hepatitis D virusoid gets the gene products and other machinery required for completion of replication.
