This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Proteins bonds and structure, Subject name: Biochemistry
Which structure of Hb can do function? 
Select and explain. 
A. Primary, secondary , teiary, B. Primary & secondary, C. Primary, secondary , teiary, quaernary, D. Teiary & quaernary
D: Teiary & quaernary
Answer: D: Teiary & quaernary 
Explanation: In case of any protein, Primary & secondary structures -NO function. Function stas from Teiary structure.