This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
Oncogenic RNA virus is - 
Select and explain. 
A. An leukosis virus, B. Herpes virus, C. Adenovirus, D. Togavirus
A: An leukosis virus
Answer: A: An leukosis virus 
Explanation: only an leukosis viruse are RNA viruses(retro virus)others are DNA virus REF:MICROBIOLOGY ANANTHA NARAYANAN NINTH EDITION PAGE.565