Which of the following antigens is responsible for the phenomenon of 'hemolytic disease of the newborn' (HDN) due to Rh incompatibility between mother and fetus?

The RhD antigen is the primary antigen responsible for Rh incompatibility and hemolytic disease of the newborn (HDN). If an Rh-negative mother is sensitized to RhD-positive fetal red cells during pregnancy or childbirth, she may produce anti-RhD antibodies that can cross the placenta and destroy the red blood cells of an RhD-positive fetus in a subsequent pregnancy.