This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Pediatrics
Which of the following hemoglobin (Hb) estimation will be diagnostically helpful in a case of beta thalassemia trait? 
Select and explain. 
A. Hb-F, B. HbA, C. HbA2, D. Hb-H
C: HbA2
Answer: C: HbA2 
Explanation: c. HbA2(Ref: Nelson's 20/e p 2349, Ghai 8/e p 341)Hb electrophoresis findings in Thalassemia:Type of Hbb thalassemia majorb-Thalassemia traitHbADecreased90-96%HbA25-7%3.5-7%HbF10-100%1-5%