This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Physiology
Who described conditioned reflex: 
Select and explain. 
A. Pavlov, B. Salk, C. Sherrington, D. Priestly
A: Pavlov
Answer: A: Pavlov 
Explanation: Ans. A. PavlovIVAN PETROVICH PAVLOV was a Russian physiologist. He won the Nobel Prize in medicine in 1904. He is remembered particularly for his work on conditioned response.