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
The most common coagulation disorders haemophilia A and Von WilLebrand's disease are due to 
Select and explain. 
A. Factor IX deficiency, B. Vitamin K deficiency, C. Factor X deficiency, D. Factor VIII deficiency
D: Factor VIII deficiency
Answer: D: Factor VIII deficiency 
Explanation: None