Final answer:
An individual with A antigens on their RBCs and no B antigens has the ABO blood type A. The ABO blood type is determined by the presence of antigens A and B, and blood type A individuals would have antibodies against B antigens.
Step-by-step explanation:
An individual with A antigens on their red blood cells (RBCs) and no B antigens has the ABO blood type A. People with blood type A have A antigens on the surface of their erythrocytes and form anti-B antibodies in their blood plasma. These antibodies would react against any B antigens, should they be present. Blood type A is therefore incompatible with blood type B or AB due to the potential for antibody reaction but compatible with blood type O, which lacks both A and B antigens on the erythrocytes.
The ABO blood typing system is determined by the presence or absence of two antigens, A and B. Individuals with both antigens are type AB, individuals with neither antigen are type O, and as stated, individuals with only A antigens are type A.