The correct answer is predatory birds.
The flowing of toxic chemicals and heavy metals into the water body when the agricultural, industrial, and human wastes run off or are discharged intentionally into the water body is known as biomagnification. These pollutants result in genetic mutations, disease, reproductive difficulties, birth defects, death, and behavioral modifications in various marine species.
However, the extremity of the destruction varies significantly among the species. In various circumstances, the animals close to the top of the food chain are most influenced by the procedure of biomagnification.
Several of the harmful toxins get settle at the lower level in a water body and are then consumed by the species, which feed or live on the bottom dwellers. As these constituents are not digested, they gathered inside the bodies of the species, which consumes them.
It signifies that the higher level predators, like fish, birds, or marine mammals accumulate more harmful concentrations of toxic substances in comparison to the animals lower on the food chain. Thus, in the given case, the more concentrated amount of toxins would be found in the predatory birds.