Which statement best describes genetic drift and gene flow?

• A. Drift is natural selection driving allele frequencies toward advantageous traits.
• B. Gene flow is the random fluctuation of allele frequencies in a population.
• C. Drift is random changes in allele frequencies in small populations; gene flow is the movement of alleles between populations.
• D. Both drift and gene flow increase genetic differences between populations over time.

Answer: (C)