This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Pediatrics
Hemophilia A results due to deficiency of which of the factors: 
Select and explain. 
A. II, B. VII, C. VIII, D. XI
C: VIII
Answer: C: VIII 
Explanation: Ans. C. VIIIHaemophilia's are the most common hereditary clotting defects occurring as X-linked recessive disorders. Haemophilia A is caused by factor VIII deficiency and haemophilia B due to factor XI deficiency: