Which of the following occur at the same trophic level?

The step or position in a nutritive series like food chain is referred to as trophic level.

There are different trophic levels in an ecosystem and food chain. The producers (photosynthetic organisms) form the first trophic level and consumers take up the successive trophic levels.

The plants or producers take up the primary trophic level. The animals that consume plant/producers take up the secondary trophic levels like deer, cow, bee, earthworm. Animals feeding on the animals of secondary trophic level are considered tertiary trophic level. E.g., snake, frog, crow.