Which process contributes to genetic variation in a population?

Horizontal gene transfer is a significant mechanism that contributes to genetic variation within a population, particularly among microorganisms such as bacteria. This process allows for the direct transfer of genetic material between different organisms, which can occur through various methods, including transformation (uptake of naked DNA), transduction (via bacteriophages), and conjugation (direct transfer through cell contact).

This genetic exchange can introduce new traits and increase genetic diversity, thereby enhancing a population's adaptability to environmental changes, resistance to diseases, and other evolutionary pressures. In contrast, asexual reproduction, cloning, and genomic imprinting do not typically enhance genetic diversity; instead, they often lead to the preservation of existing genetic material without introducing new variations.