The ABO Blood Groups in Humans Are Determined by a Multiple-Allele

Multiple Choice

The ABO blood groups in humans are determined by a multiple-allele system in which I^A and I^B are codominant and are both dominant to I^O.If an infant born to a mother with blood type O is also type O, the father's blood type can be

A) only O or A.
B) only A or B.
C) only O.
D) O, A, or B.
E) impossible to determine.