One week following extraction of teeth 1.8 and 4.8, an 18 year old male returns to the dental office complaining of persistent bleeding from the extraction sites. The medical history was unremarkable, except for episodes of bruising and joint swelling as a child. Subsequent blood tests showed normal bleeding time and a factor VIII level of 14%. The most likely cause would be

ibuprofen intake

Hemophilia A.

dry socket

Vitamin K deficiency

cirrhosis