Answer:
Hawk
Step-by-step explanation:
Biomagnification can be described as the accumulation of substances like toxins, pesticides etc in tolerant organisms. The biomagnification tends to increase as the trophic levels of a food chain increase. This is because these substances get more and more accumulated as they move up a food chain.
In the example of the food chain mentioned in this question, the highest trophic level is of hawks, so they will be subjected to the greatest biomagnification.