A Group O,D-Positive Mother Gave Birth to an A-Negative Infant

A group O,D-positive mother gave birth to an A-negative infant.After 24 hours,the newborn's bilirubin level rose to 19 mg/dL.A direct antiglobulin test performed on the cord blood specimen was positive with anti-IgG.What is the most probable antibody causing this?

A) Anti-D
B) Anti-A
C) Anti-B
D) Anti-A,B