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: Biochemistry
[{'content': 'Platelet adhesion to collagen occurs : \nSelect and explain. \nA. Factor VIII, B. Factor IX, C. von Willebrand factor, D. Fibronectin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Platelet adhesion to collagen occurs von-Willebrand factor)Endothelial injury allows platelets to contact the underlying extracellular matrix; subsequent adhesion occurs through interactions with von Willebrand factor (vWF), which is a product of normal endothelial cells and an essential cofactor for platelet binding to matrix elements.', 'role': 'assistant'}]