Which of the following statement is not true about Von willebrand disease?: (A) VWF is synthesized by endothelial cells and megakonjocytes, (B) VWF maybe located in the plasma and subendothelial tissue, (C) VWF causes platelet adhesion and prevents degradation of factor VIII in plasma, (D) Deficiency of VWF causes prolonged prothrombin time
Answer is D. Laboratory findings of Von willebrand disease

Platelet count : Normal 
Bleeding time : Prolonged
Clotting time : Prolonged
Prothrombin time : Normal