(N/A) According to the Law of Dominance,in a heterozygous condition,the trait that expresses itself in the $F_{1}$ generation is called the dominant trait,while the trait that remains masked is called the recessive trait.
In this cross,the $F_{1}$ generation consists of $Tt$ genotypes,all of which are tall. This indicates that the allele for tallness $(T)$ is dominant over the allele for shortness $(t)$.
Even though both alleles are present in the $F_{1}$ generation,only the dominant trait $(T)$ is phenotypically expressed. The recessive trait $(t)$ only expresses itself in the $F_{2}$ generation when it is present in a homozygous condition $(tt)$.