What is the significance of the Hh blood group system in relation to the secretion of ABO blood group antigens?

A It determines the presence or absence of ABO antigens in saliva and other bodily fluids ✓
B It influences the severity of hemolytic disease of the newborn
C It affects the expression of Rh blood group antigens
D It has no relation to ABO blood group antigen secretion

Explanation

The Hh blood group system controls the secretion of ABO blood group antigens in bodily fluids, such as saliva, and is important in determining an individual's secretor status.

Source

Modern Blood Banking and Transfusion Practices
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Medium MEDICAL Confidence: high