The correct answer is B. Drought
Step-by-step explanation:
In biology, density-dependent factors are factors that directly depend on the population of organisms, this includes factors such as predators, diseases, resources availability or space that affect the size of a population by limiting it. For example, more organisms lead to little food availability and this leads to a decline in the number of organisms limiting population growth. On the other hand, factors that are not density-dependent are not related to the size of a population but can affect populations of any size. Considering this, the one that is not a density-dependent factor is drought as this is a natural disaster that can affect any population and is not related to the size of populations.