Question

this passage describes the tobiano patterning trait in horses: the tobiano pattern is a type of coat pattern in horses. horses with tobiano patterning have white legs and rounded white patches on their bodies. their tails may also have a mix of white and colored hairs. in a group of horses, some individuals have tobiano patterning and others do not. in this group, the gene for the tobiano patterning trait has two alleles. the allele b is for having tobiano patterning, and the allele b is for not having tobiano patterning. dallas, a horse from this group, does not have tobiano patterning. dallas has two alleles for not having tobiano patterning. based on this information, click the blue words to correct any errors in the text. dallas does not have tobiano patterning. this is dallass genotype for the tobiano patterning trait. dallas is heterozygous for the tobiano patterning gene. dallass genotype for the tobiano patterning gene is bb.

Explanation:

The allele $B$ is for having Tobiano patterning and $b$ for not having it. Dallas has two alleles for not having Tobiano patterning, so its genotype is $bb$. A heterozygous individual has two different alleles ($Bb$), but Dallas has two of the same ($b$) alleles, so it is homozygous recessive.

Answer:

The error is in "Dallas is heterozygous for the Tobiano patterning gene." It should be "Dallas is homozygous for the Tobiano patterning gene."