Question

a) adaptation
b) natural selection
c) speciation
d) limiting factor
anything in the environment that can limit the growth or survival of a population.

Explanation:

A limiting factor is an environmental condition that restricts the growth, distribution, or survival of an organism or a population within an ecosystem. Adaptation is a trait that helps an organism survive and reproduce. Natural selection is the process by which organisms better adapted to their environment tend to survive and produce more offspring. Speciation is the formation of new and distinct species in the course of evolution.

Answer:

D. limiting factor