In the context of a food web, organisms that are at the top of the food chain typically accumulate the highest levels of pesticides and other toxins due to a process known as biomagnification. This means that as one organism consumes another, any toxins present in the prey accumulate in the predator's body.
Given the options you provided, the hawk is the top predator in this scenario. Therefore, the hawk would accumulate the highest levels of pesticide among the organisms listed.
So, the correct answer is:
Hawk