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: Pathology
In 13- thalassemia - 
Select and explain. 
A. Excess chain, B. No 13 chain, C. No chain, D. Normal chains
B: No 13 chain
Answer: B: No 13 chain 
Explanation: Ans. is 'b' i.e., No 13 chain