<prompt> All are oncogenic viruses except-HBVHPVEBVVZV  <response>: Ans. is d i.e., VZV o Many viruses have been implicated in the causation of cancers :A RNA viruses All oncogenic RNA viruses belong to family retroviriadae retroviruses. Important examples are Avian leukosis virus, murine leukosis virus, murine mammary tumor virus, HIV causing AIDS related malignancies and Human-T-cell leukemia virus causing Adult T-cell leukemia.B DNA viruses DNA viruses causing cancers are1 Papillomaviridae HPV: Causes genital tumors, SCC and oropharyngeal carcinoma.2 Herpesviridae : These viruses are :i HSV-2: Causes cervical carcinoma.ii EBV: Causes nasopharyngeal carcinoma and Burkitts lymphoma.iii HHV-8: It causes Kaposis sarcoma.3 Hepadnaviridae HBV: It causes hepatocellular carcinoma.4 Flaviviridae HCV: It causes hepatocellular carcinoma. 