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Mr. Smith is a dog breeder who specializes in Dalmations. Unfortunately, there is a common recessive defect among this breed that results in deafness. Mr. Smith has a new male dog that he would like to use for breeding purposes, but he suspects the male dog may carry the deafness gene. What kind of a breeding test cross would be likely to help him figure out the male's genotype?
If he crossed the male with a deaf female dog, and any of the puppies are deaf, then the male carries the gene.