In a maternity ward, four babies become accidentally mixed up. The ABO blood types of the four babies are known to be. Baby Jane is O, Baby John is A, Baby Christopher is B, and Baby Robin is AB. The ABO types of the four sets of parents are determined as such: The Anderson's are AB and O, the Browns are A and O, the Christiansons are A and AB, and the Dietrichs are O and O. Indicate which baby belongs to eat set of Parents.

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Explanation:

We inherit our blood groups from both parents. Our blood type is controlled by a single gene. This gene displays 3 different allelic pairs which must include A, B or O.  A child is expected to receive one of the three possible allelic pairs from each of the both parents. This means that there are six possible genotype and four possible phenotype for the child.

Given that Christopher's parents (Andersons) are AB and O,Christopher can have a B blood group.

Given that John's parents (Browns) are A and O, it explains how John can have blood group A.

Given that The Christiansons are A and AB, they can give birth to Robin whose blood group is AB.

Since the Dietrichs are O and O, the only possible blood group of their child is O, hence they are definitely the parents of Jane.