CBSE Class 10 Science 2018 · Paper 31(B)/C · Question 5

Trophic levels are the various steps (levels) in a food chain at which the transfer of food, and so of energy, takes place; each organism in a food chain occupies one trophic level. A food chain of four trophic levels: Grass $\to$ Grasshopper $\to$ Frog $\to$ Snake (producer $\to$ primary consumer $\to$ secondary consumer $\to$ tertiary consumer)