Final answer:
Option C) A flower has a long stem and a white color describes a possible phenotype, which refers to observable characteristics, such as physical traits that can be seen like flower color and stem length.
Step-by-step explanation:
The phenotype of an organism refers to its observable characteristics, which result from the interactions of its genotype with the environment. So, when a student asks about a possible phenotype, they're referring to a trait that can be seen or measured.
Among the provided options, a direct answer to which describes a possible phenotype is option C) A flower has a long stem and a white color. This statement describes physical attributes of the flower that you can observe, which fits the definition of a phenotype. The other options either refer to an organism's capability (A), which is not a direct observable characteristic, or to genetic makeup (B and D), which is known as the genotype, not the phenotype.
Examples of phenotypes include flower color, as in red (RR), white (WW), or pink (RW) flowers from the given information, or the fur color in rabbits (brown for the wild-type C+C+, black-tipped white for chinchilla cchcch, black extremities and white elsewhere for Himalayan chch, and all-white for albino cc).