Proper development and hearing in humans is controlled by two sets of alleles: D/d affect the proper development of the middle ear, while E/e affect the inner ear. A homozygous condition of either of the recessive alleles (d or e) cause congenital deafness when both are present. Because normal hearing requires the proper functioning of both parts of the ear (middle and inner), both dominant alleles, D and E, must be present for normal hearing. Give the phenotype (normal hearing or deaf) results for each of these crosses:
a) DdEE x DdEE b) DdEe x DdEe c) ddEE x DDee d) DdEE x Ddee e) DdEE x DDEe