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: Pathology
[{'content': 'Which of the following statements about Hemoglobin S (HbS) is not true? \nSelect and explain. \nA. Hemoglobin HbS differs from hemoglobinbHbA by the substitution of Val for Glu in position 6 of the beta chain, B. One altered peptide of HbS migrates faster towards the cathode (-) than the corresponding peptide of HbA, C. Binding of HbS to the deoxygenated HbA can extend the polymer and cause sickling of the red blood cells, D. Lowering the concentration of deoxygenated HbS can prevent sickling', 'role': 'user'}, {'content': 'Answer: C \nExplanation: . Binding of HbS to the deoxygenated HbA can extend the polymer and cause sickling of the red blood cells', 'role': 'assistant'}]