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
RNA dependent DNA polymerase is found in: 
Select and explain. 
A. Retrovirus, B. Rota-virus, C. Reo-virus, D. All of the above
A: Retrovirus
Answer: A: Retrovirus 
Explanation: Ans. A. RetrovirusRetroviruses: -a. Positive stranded RNA virusesb. Have a diploid genomec. 100 nm in diameterd. Possess reverse transcriptase enzyme (RNA dependent DNA polymerase) as they replicate through a DNA intermediate.