Answer:
The answer is option number 3. "Climax community"
Step-by-step explanation:
The term that best relates to equilibrium is "climax community." A climax community is the final and stable stage of succession, where the community of organisms is in a state of equilibrium with its environment. This community is characterized by a diverse array of species that have reached a balance in their population sizes and interactions with one another and the environment. In other words, the climax community represents a state of ecological balance or equilibrium. In contrast, primary succession and secondary succession refer to the initial stages of succession in a newly formed or disturbed environment, while pioneer species are the first organisms to colonize such environments.
I hope this might help.