Final answer:
An ecosystem is a community of living organisms and their interactions with their abiotic environment. Beneficial interdependencies are one of the ways species interact within an ecosystem.
Step-by-step explanation:
An ecosystem is a community of living organisms and their interactions with their abiotic (non-living) environment. These interactions can be beneficial interdependencies, meaning that different species rely on each other for resources and survival. For example, bees and flowers have a beneficial interdependency, where bees rely on the nectar from flowers for food, while flowers rely on bees for pollination. Therefore, option c. Ecosystems are made up of beneficial interdependencies is the true statement regarding an ecosystem.