This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
RNA oncogenic virus is: September 2004 
Select and explain. 
A. Human papilloma virus, B. Epstein Barr virus, C. Human T-cell leukemia virus, D. Hepatitis B virus
C: Human T-cell leukemia virus
Answer: C: Human T-cell leukemia virus 
Explanation: Ans. C i.e. Human T-cell leukemia virus The human T-lymphotropic virus, human T-cell lymphotropic virus, or human T-cell leukemia-lymphoma virus (HTLV) family of viruses are a group of human retroviruses that are known to cause a type of cancer called adult T-cell leukemia/lymphoma and a demyelinating disease called HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP).