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: Pathology
Bleeding time is abnormal in: 
Select and explain. 
A. Haemophilia, B. Christmas disease, C. Von-Willebrand disease, D. Vitamin K-deficiency
C: Von-Willebrand disease
Answer: C: Von-Willebrand disease 
Explanation: (Von Wille brand's disease): Ref: 649-R, 428-HM BLEEDING TIME: - This test is dependent upon capillary function as well as on platelet number and ability of platelets to adhere to form aggregates (Normal range - 3-8 minutes) Prolong bleeding time may be due to: 1. Thrombocytopenia 2. Disorder of platelet function 3. Von Willebrand's function 4. Vascular abnormalities (eg. Ehler-Danlos syndrome) 5. Severe - deficiency of factor V and XI