An example of using a population approach is:
S.) Studying the entire food chain that leads to a top predator.
This option represents a population approach because it involves examining the relationships and interactions among various species within an ecosystem. It looks at how different species (including a top predator) are connected through their feeding relationships, thus focusing on the dynamics of populations within a broader ecological context. This approach is integral in understanding the structure and functioning of ecosystems, and how changes in one part of the food chain can impact the entire system.