Why is genetic drift considered a random process?

Genetic drift is considered a random process because it stems from the random sampling of individuals in a population that contributes to the next generation's gene pool. In essence, genetic drift occurs when certain alleles (variations of a gene) become more or less common purely by chance, rather than through selection pressures or deliberate actions. This randomness can lead to significant changes in allele frequencies over time, especially in small populations where the effects of chance events can have a more pronounced impact.

For example, if a natural disaster randomly wipes out a portion of a population, the alleles carried by the survivors may not be representative of the original population's genetic makeup. Consequently, this can lead to changes in genetic diversity and allele frequencies that do not follow predictable patterns, thereby reinforcing the notion of randomness inherent in genetic drift.

Other options imply deterministic factors or characteristics that do not accurately define genetic drift, as it is fundamentally characterized by its unpredictability in how allele frequencies change over generations.