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: Pediatrics
Hb A2 concentration in thalassemia trait is – 
Select and explain. 
A. 1, B. 1–2.5, C. 2.5–3.5, D. >3.5
D: >3.5
Answer: D: >3.5 
Explanation: None