A pesticide which is a chlorinated hydrocarbon is sprayed on a food crop. The food chain is:
Food crop → Rat → Snake → Hawk.
In this food chain, the highest concentration of the pesticide would accumulate in which one of the following?

Correct Option

The phenomenon described is biomagnification, also known as bioamplification. Chlorinated hydrocarbons are persistent, non-biodegradable pesticides that accumulate in the tissues of organisms. As these substances are not metabolized or excreted, their concentration increases progressively at each successive trophic level in a food chain. In the given food chain (Food crop → Rat → Snake → Hawk), the hawk occupies the highest trophic level (tertiary consumer/top predator). Consequently, it will exhibit the highest concentration of the pesticide due to the cumulative effect of biomagnification through the lower trophic levels.

Incorrect Options

• Food crop: As the primary producer, the food crop represents the initial entry point of the pesticide into the food chain. It would contain the lowest concentration of the pesticide.
• Rat: As a primary consumer, the rat ingests the pesticide from the food crop. Its body would accumulate a higher concentration than the food crop but a lower concentration than the snake or hawk, which are at higher trophic levels.
• Snake: As a secondary consumer, the snake preys on rats. It would accumulate a higher concentration of the pesticide than both the food crop and the rat, but a lower concentration than the hawk, which is at a higher trophic level.