The correct answer is B. Density-independent
Step-by-step explanation:
In biology, regulation occurs as there are factors that influence the number of individuals of a species as well as the fertility or death rate of it. In the case of density-independent regulation, this describes factors that are not linked to the population density of a species but instead can affect populations of all sizes this includes weather conditions and natural disasters including fires. This differs from density-dependent regulation that occurs depending on the population such as predation, certain diseases or predation. Considering this, it can be concluded a forest fire is an example of density-independent regulation because it regulates the size of the population by increasing death rate but does not depend directly on the population.