The Underlying Molecular Basis for Distinguishing Blood-Group Antigens A,B and O

Multiple Choice

The underlying molecular basis for distinguishing blood-group antigens A,B and O is _____ at the erythrocyte surface.

A) the presence or absence of fucose in glycolipids
B) differences in the oligosaccharide attached to the lipid ceramide
C) structural polymorphisms in the Rhesus D antigen
D) the levels of MHC class I and class II molecules.