Awoman gives birth to a son who has type ab blood. she has type b blood. which of the following can be concluded from this about her parents blood type? a.) one of her parents had at least one b allele b.) one of her parents had type ab blood. c.) one of her parents had type b blood and the other type a blood. d.) one of her parents had at least one a allele and the other at least one b allele.