This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
All are true regarding fetal RBC&;s Except - 
Select and explain. 
A. Elevated 2,3 DPG, B. Decreased carbonic anhydrase activity, C. Decreased life span, D. High RBC volume
A: Elevated 2,3 DPG
Answer: A: Elevated 2,3 DPG 
Explanation: <p>The difference in physiochemical propeies when compared with Hb A are: increased solubility of deoxy HbF,slower electrophoretic mobility for HbF,increased resistance of UnFounately to alkali denaturation,HbF has decreased interaction with 2,3-BPG.Thus increase in oxygen affinity is physiologically advantageous in facilitating transplacental oxygen transpo due to diminished binding of 2,3-BPG.</p><p>Reference :DM Vasudevan textbook of biochemistry sixth edition pg no 259</p>