Answer : The correct answer is -
The rodents mutate a new allele for gray hair.
A population is said to be in the Hardy Weinberg equilibrium when it follows the following five conditions -
1) There should be no mutation.
2) No gene flow should be there in the population.
3) Population size should be large.
4) There should be random mating in the population.
5) No natural selection should operate on the population.
According to this information, we can conclude that last option in the question will cause the rodent population not to be in the Hardy Weinberg equilibrium.
