A Blood Sample from a 90-Year-Old Man Was Submitted to the Blood

Multiple Choice

A blood sample from a 90-year-old man was submitted to the blood bank for a type and screen before surgery.The forward type demonstrates as a group A,whereas the reverse type appears to be group AB.What is the most likely cause of the discrepancy?

A) Contaminated reagent antisera
B) Rouleaux formation
C) That the patient has autoantibodies
D) That patient has low-titer isoagglutinins