Which of the following best defines genetic diversity?

• A. The variety of genes in a population
• B. The uniformity of traits in a species
• C. The fixed expression of certain traits
• D. The occurrence of recessive traits only

Answer: (A)

Genetic diversity refers to the variety of genes within a population, encompassing the different alleles and genetic combinations that exist among individuals. This genetic variation is essential for the adaptability and survival of a species, as it allows populations to respond to changes in the environment, resist diseases, and cope with other ecological pressures. A higher level of genetic diversity can enhance a population's evolutionary potential, making it more resilient to challenges.

In contrast, the other options suggest concepts that are antithetical to genetic diversity. For example, uniformity of traits implies a lack of variation, which directly contradicts the notion of genetic diversity. Similarly, a fixed expression of certain traits indicates a restricted genetic variability, and the occurrence of recessive traits only narrows the focus to specific alleles while ignoring the broader gene pool. Thus, the correct answer highlights the fundamental aspect of genetic variation that underlies the health and resilience of populations.