Rats belong to the secondary consumer trophic level.
Explanation: In an ecosystem, organisms can be categorized into different trophic levels based on their feeding relationships. Primary producers, such as plants and algae, form the base of the food chain, providing energy through photosynthesis. Herbivores, which consume these plants, are classified as primary consumers, while organisms that eat herbivores are known as secondary consumers. Rats are typically omnivorous and can eat both plant material and smaller animals, allowing them to fit into the secondary consumer category, feeding on primary consumers like insects and small mammals. This placement within the food web highlights their role in the energy transfer and nutrient cycling in their ecosystems.