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: Biochemistry
The helical structure model of two polynucleotide chains of DNA was proposed by 
Select and explain. 
A. Guerin, B. Craig venter, C. Watson and Crick, D. Michael Bishop and Harold Warms
C: Watson and Crick
Answer: C: Watson and Crick 
Explanation: None