The expected genotypic ratios are 0BB: 2Bb : 2bb. The 1st option is correct.
The Mendelian theory by George Mendel explains the monohybrid experiment crossing which can be achieved by the use of punnet square.
From the given information, in cocker spaniels
If a brown cocker spaniel i.e bb (recessive trait) is crossed with a heterozygous black cocker spaniel i.e. Bb
Then, we can use the punnet square to determine their genotypes.
b b
B Bb Bb
b bb bb
Therefore, we can conclude that the genotypic ratios are 0BB: 2Bb : 2bb
Learn more about monohybrid crossing here:
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