This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Heart, Circulation, and Blood, Subject name: Physiology
[{'content': 'Which of the following has strong affinity for hemoglobin and acts in blood to act as "mop-up" molecule to bind hemoglobin? \nSelect and explain. \nA. Ferritin, B. Transferrin, C. Haptoglobin, D. Albumin', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. c (Haptoglobin). (Ref. Robbin, Pathology, 7th ed., 624; Harrison, Internal medicine 15th ed., s608)Free Hb in plasma is promptly bounded by an alphal globulin, the haptoglobin that acts as 'mop-up' producing a complex that is rapidly cleared by mononuclear phagocyte system, thus preventing excretion in urine; hence in intravascular hemolysis serum haptoglobin is decreased.GENERAL FEATURES OF HEMOLYTIC DISORDERSGeneral examinationJaundice, pallorOther physical findingsSpleen may be enlarged; bossing of skull in severe congenital casesHemoglobinFrom normal to severely reducedMCV, MCHUsually increasedReticulocytesIncreasedBilirubinIncreased (mostly unconjugated)LDHIncreased (up to 10X normal with intravascular hemolysis)HaptoglobinReduced to absent", 'role': 'assistant'}]