Which term refers to the external, observable expression of a particular trait in an organism?

1. The external expression of a trait, such as tall or dwarf, is called the phenotype. 2. The genetic make-up that underlies it, such as TT or Tt, is the genotype, which rules out option A. 3. So the observable expression is the phenotype, option B. _Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 18 Genetics "Monohybrid Cross", p.269_