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: Surgery
[{'content': 'Post extraction bleeding in a leukaemic patient is due to: \nSelect and explain. \nA. Increase in leukocytes, B. Low calcium level, C. Platelet disorder, D. Deficiency of clotting factors', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]