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: Social & Preventive Medicine
For studying the complete amino acid sequence of two polypeptide chains of Insulin, Nobel Prize was awarded to 
Select and explain. 
A. Fredreich Sanger, B. Banting and Macleod, C. Paul Muller, D. Alexander Fleming
A: Fredreich Sanger
Answer: A: Fredreich Sanger 
Explanation: LIST OF FEW NOBEL LAUREATES IN PHYSIOLOGY OR MEDICINE

Sir Ronald Ross: Life cycle of Plasmodium
I.P. Pavlov: Physiology of digestion
Robert Koch: Discoveries in Tuberculosis
Paul Ehrlich: Immunity
F.G. Banting & J.J.R. McLeod: Insulin
Willem Einthoven: ECG
Karl Landsteiner: Human blood groups
Sir Alexander Fleming: Penicillin
Paul H. Muller: DDT
S.A. Waksman: Streptomycin (First antibiotic, against TB)
Har Gobind Khorana: Interpretation of genetic code
Sir Godfrey N. Hounsfield: CT scan
J.E. Murray & E.D. Thomas: Organ and cell transplantation
Sir Peter Mansfield: MRI
B.J. Marshall & J.R. Warren: H. pylori; its role in peptic ulcer disease
H.Z. Hausen: HPV causing cervical cancer
F.B. Sinnoussi & L. Montagnair: HIV
Robert G. Edwards: In-vitro fertilization