How does genetic drift primarily operate in small populations?

Genetic drift in small populations primarily operates through random changes in allele frequencies due to chance, which is encapsulated in the correct answer. In small populations, the impact of random events is amplified, meaning that the loss or fixation of alleles can occur simply due to sampling error. For instance, if a few individuals randomly reproduce more than others, the alleles carried by those individuals will become more prevalent in the next generation, regardless of any selective advantage they may confer.

This randomness can lead to significant shifts in genetic composition over generations, especially if a population is small enough that each individual carries a considerable fraction of the total genetic variation. Over time, genetic drift can reduce genetic diversity and potentially lead to the establishment of certain alleles at random, sometimes even those that do not confer any advantage or could even be disadvantageous.

The other options do not appropriately describe the mechanism of genetic drift. Increasing genetic diversity through mutation pertains more to the origin of new alleles rather than changes in existing allele frequencies due to drift. Rapidly eliminating all recessive alleles would suggest a selective process rather than a random one, which is contrary to the essence of genetic drift. Favoring alleles that provide a survival advantage describes natural selection rather than drift, where chance