Which of the following conditions is NOT part of the Hardy-Weinberg Equilibrium assumptions?

The correct answer reflects a condition that does not align with the assumptions of Hardy-Weinberg Equilibrium. In this model, one of the key assumptions is that the population must be large enough to prevent genetic drift, which can significantly affect allele frequencies in small populations. When a population is small, random events can lead to major swings in allele frequencies over generations, deviating from the equilibrium.

In contrast, the other conditions explicitly align with the Hardy-Weinberg principles. No genetic mutations must occur to maintain stable allele frequencies. Additionally, there should be no immigration or emigration, ensuring that the population remains closed to gene flow. Lastly, random mating is critical to prevent certain traits from being preferentially selected or eliminated, allowing allele frequencies to remain constant. Hence, the assumption regarding a small population size is not a requirement for Hardy-Weinberg Equilibrium, making it the distinct choice.