In pea plants, the allele for tallness is dominant. What are the possible genotypes of a tall pea plant?

TT or Tt

Tt or tt

TT or tt

TT only

TT or Tt, because there has to be a dominant allele in the genotype in order for tallness to be expressed at all, but with the given information, the two plants needed to create this one has one tall plant and the other could be tall or short ... either way, the outcome will always be tall with one tall "parent"

TT or Tt because even though the second letter is not dominant the first one is greater