Final answer:
Gene families most commonly arise via gene duplication, where an entire gene is copied in the genome. This allows for genetic diversity and the potential for new gene functions to evolve while retaining the original gene's function.
Step-by-step explanation:
Gene families can arise by several mechanisms, but the options provided concern different biological processes. The correct mechanism by which gene families can arise is C. Gene duplication. Gene duplication occurs when an entire gene is copied, resulting in additional gene copies in the genome. These extra copies can undergo mutations over time, allowing for the evolution of new functions while the original gene continues its existing function.
Gene Expression and Variation
Gene expression involves the process of transcription and translation, where information from DNA is transcribed into RNA and then translated to form proteins. Variation among offspring can come from genetic recombination, fertilization, and meiosis, which involve processes like crossing over and random chromosome assortment.
Genetic Recombination
Genetic recombination, which can play a role in the formation of gene families, occurs through processes such as independent assortment and crossing over during meiosis.