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': 'Patient with hemophilia A have bleeding disorder because of \nSelect and explain. \nA. Lack of platelet count, B. Lack of platelet adhesion, C. Lack of factor VIII a during activation of factor X in coagulation coscade, D. Release of thromboxane A2', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Hemophilia A\nX - linked disorder\n\n90% cases - deficiency of factor 8\n10% cases functional defect of factor 8\n\nFactor VIII a complex is the most important activator of factor X required for conversion of prothrombin to thrombin.', 'role': 'assistant'}]