Tallness is dominant.
Homozygous (purebred) tall would be
a. TT
B. Tt
C. tt
a. TT
Heterozygous (hybrid) for tall would be
a. TT
B. Tt
C. tt
B. Tt
To determine the answer, we need to understand the concept of dominance in genetics. In this case, tallness is stated to be dominant. This means that if an individual has at least one allele for tallness, they will exhibit the tall phenotype.
Now, let's move on to the options provided:
A. TT: This genotype represents two copies of the tall allele. Since tallness is dominant, an individual with the genotype TT will be tall. This option represents homozygous (purebred) tall.
B. Tt: This genotype represents one copy of the tall allele and one copy of the short allele. As tallness is dominant, this individual will also be tall. However, this option represents heterozygous tall, where the individual carries both the tall and short alleles.
C. tt: This genotype represents two copies of the short allele. Since tallness is dominant, an individual with this genotype will be short. This option represents homozygous (purebred) short.
To summarize, the correct answer is A. TT, as it represents homozygous (purebred) tall individuals.