The genotype for a homozygous tall plant depends on the specific genetic system being considered. However, in the classic example of Mendelian genetics with simple dominance, the genotype would be TT.

Here's why:

* Homozygous: Means having two identical alleles for a trait.

* Tall: Represents the dominant trait.

* T: Represents the dominant allele for tallness.

Therefore, a homozygous tall plant has two copies of the dominant "T" allele, resulting in the genotype TT.