If a plant has one dominant and one recessive form for a trait, what will usually be seen externally?

Correct answer: The dominant trait will appear

The governing concept is complete dominance. A plant with one dominant allele and one recessive allele is heterozygous, for example Tt. The dominant allele determines the phenotype, so the plant generally appears tall if T represents tallness, even though the recessive allele is still present and can be passed to offspring. Hence option A is correct. The recessive phenotype requires two recessive alleles, and heterozygosity does not prevent reproduction.