What determines a blood type to be "O"

the type of surface protein.

Explanation:

On the exterior portion are trans-membrane glycoproteins are sugar residues with specific orientations that give rise to blood types. The sugar residue prevents people with different red cells from mixing.

Type O has no antigen b/c no sugar disposition - doesn't look any different to the immune system. Has antibodies against both A and B; has no antigens which means have both antibodies

i think the answer is c

hope this