Answer: b) 25
Explanation: B is a gene for blue feathers and b is a gene for red feathers, the genotype for a heterozygous bird is Bb. A cross between two heterozygous birds will produce 1BB, 2Bb and 1bb. Genotype BB and Bb will manifest outwardly as blue feathers while Bb will manifest as red feathers. Only one out of the four offsprings are red feathered. The percentage of the offsprings that are red feathered is 1/4 x 100 = 25
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