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
Patients with hemophilia a have bleeding disorder because of - 
Select and explain. 
A. Lack of platelet aggregation, B. Lack of reaction accelerator during activation of factor X in coagulation cascade, C. Neutralization of antithrombin III, D. Release of Thromboxane A2
B: Lack of reaction accelerator during activation of factor X in coagulation cascade
Answer: B: Lack of reaction accelerator during activation of factor X in coagulation cascade 
Explanation: Ans. is 'b' i.e., Lack of reaction accelerator during activation of factor X in coagulation cascade