The baby can have type A or B blood. The mother will donate either her A or B allele, and the father can only donate an O type allele. The rH factor will depend on the father. If he is positive, the baby may be too. If he is negative, the baby will be negative.
If the father and the mather has any type of blood group it may not cause the child mostly. But mast of the child has their own fathers blood group. In this way the child may have his
father's blood group that is O type blood or it may have other type of blood groups.