The virus mutation that can cause cancer in a host organism is when the mutation occurs in the genome.
Step-by-step explanation:
When cells that does not need to replicate start replicating proliferously then that particular cells become carcinogenic. A virus can cause considerable mutation in the genome of the host cells. The virus acts in the host cell alter their DNA and causes oncogenes.
Mutations in genes causes changes in the cell cycle. This creates an imbalance in the cell production where some cells undergo continuous cell division. As the cancerous cells undergoes vigorous proliferation they become malignant tumor.