To answer this question, you need to have a better understanding of the terms “phenotype” and “genotype”. The term genotype refers to the DNA makeup of an organism which determines a particular characteristic or feature (phenotype) of that organism.
On the other hand, the term phenotype refers to the observable traits in an organism such as the plant eye color, blood type, height, etc. In other words, it refers to the appearance of an organism based on a pattern of a combination of genetic traits. With that said, the correct answer to this question is "tall pea plant."
This information has actually given the phenotype of the pea plant by describing the height of the pea plant. However, it is important to note that these observable traits in an organism are highly influenced by the genotype. Phenotype is just a physical reflection of your genetic makeup.