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
[{'content': 'Feature of fetal R.B.C. - \nSelect and explain. \nA. Alkali denaturation resistant, B. Small in size, C. Has more 2,3 DPG level, D. More iron than adult RBC', 'role': 'user'}, {'content': 'Answer: A \nExplanation: <p>Fetal hemoglobin in contrast to Hb A shows the following -increased solubility of deoxy HbF, slower electrophoretic mobility for HbF, increased resistance of HbF to alkali denaturation, HbF has decreased interaction with 2,3-BPG.</p><p>DM Vasudevan textbook of biochemistry sixth edition pg no 259</p>', 'role': 'assistant'}]