Which of the following best explains why herring gull chicks were one of the first species to exhibit the effects of pollution, according to the figure?
A.
Toxins increase in concentration as one moves up a food chain.

B.
Toxins have less of an effect on herring gulls than on other species.

C.
Toxins affect terrestrial organisms more severely than aquatic organisms.

D.
Toxins decrease in concentration as one moves up a food chain.