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: Pathology
[{'content': 'Shape of RBC is biconcave due to? \nSelect and explain. \nA. Ankyrin, B. Spectrin, C. Band protein, D. Glycophorin - C', 'role': 'user'}, {'content': "Answer: B \nExplanation: The most impoant constituent of the cytoskeleton is protein spectrin. Includes alpha and beta chains.Interwined spectrin molecules are linked together by other cytoskeletal proteins and actin to form a lattice like network which is attached to the internal surface of the membrane.This network is a resilent structure which normally causes red cells to resume the biconcave disc form after forces causing distoion are removed Ref:deGruchy's clinical haematology in medical practice 6th adapted edition.page no.16 Ref Robbins 9/e pg 410", 'role': 'assistant'}]