Which of the following is an example of a phenotype?

• A. Presence of a dominant allele
• B. Homozygous recessive alleles
• C. Genetic mutation in DNA
• D. Blue eye color

Answer: (D)

Verified step by step guidance

1. Understand the concept of phenotype: A phenotype refers to the observable characteristics or traits of an organism, such as its morphology, development, biochemical properties, physiology, and behavior. These traits result from the expression of an organism's genes as well as the influence of environmental factors.
2. Differentiate between genotype and phenotype: Genotype refers to the genetic makeup of an organism, the information contained within its DNA. Phenotype is the expression of that genetic information, influenced by environmental factors, resulting in observable traits.
3. Identify examples of phenotypes: Phenotypes include traits like eye color, hair color, height, and other physical characteristics. These are the visible or measurable expressions of the genetic information.
4. Examine the options provided: Presence of a dominant allele, homozygous recessive alleles, and genetic mutation in DNA are all related to genotype, which is the genetic makeup. Blue eye color is an observable trait, making it a phenotype.
5. Conclude with the correct identification: Blue eye color is the correct example of a phenotype, as it is an observable characteristic resulting from the expression of genetic information.