Labrador retrievers may be black, brown (chocolate), or golden (yellow) in color (see chapter-opening photo). While each color may breed true, many different outcomes are seen when numerous litters are examined from a variety of matings where the parents are not necessarily true breeding. Following are just some of the many possibilities. (a) black x brown → all black (b) black x brown → 1/2 black 1/2 brown (c) black x brown → 3/4 black 1/4 golden (d) black x golden → all black (e) black x golden → 4/8 golden 3/8 black 1/8 brown (f) black x golden → 2/4 golden 1/4 black 1/4 brown (g) brown x brown → 3/4 brown 1/4 golden (h) black x black → 9/16 black 4/16 golden 3/16 brown Propose a mode of inheritance that is consistent with these data, and indicate the corresponding genotypes of the parents in each mating. Indicate as well the genotypes of dogs that breed true for each color.