If an Rh- mother becomes pregnant, when can erythroblastosis fetalis not possibly occur in the child?
A. If the child is Rh+
B. If the father is Rh+
C. If the child is Rh-
D. It will occur no matter what
Your answer is C. Because D is automatically out, B and A risk erythroblastosis fetalis occurring but if the mother and the baby are both Rh- then nothing happens since they are of the same group