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: Microbiology
”HOT SPOT” is the region of antibody which is also called 
Select and explain. 
A. hinge portion, B. hypervariable region, C. constant region, D. disulphide bond rich region
B: hypervariable region
Answer: B: hypervariable region 
Explanation: None