Male, 18 years old, recurrent epistaxis and petechia since childhood. The results of laboratory test were prolonged bleeding time,decreased platelet adhesion,decreased platelet aggregation induced by ristocetin, prolonged APTT, with normal PT, and platelet count (150×10
A.Hemophilia B.von Willebrand Disease C.Allergic purpura D.Vitamin K deficiency E.Hereditary hemorrhagic telangiectasia