All of the following are important factors affecting the Hardy-Weinberg equilibrium, except __________.

1. migration
2. temperature
3. mating patterns
4. population size

The correct option is B temperature

Hardy - Weinberg equilibrium is attained when the allele frequencies in a population are not altered for a long time, which proves that population is not evolving. There are certain factors that can affect the equilibrium such as mutations, selective mating, migration and genetic drift.
Temperature is a physical factor that has no direct effect on the frequency of alleles in a gene pool.