Which of the following entities monitors Delaware's groundwater for signs of pesticide contamination?

The Pesticide section is the correct entity that monitors Delaware's groundwater for signs of pesticide contamination. This section is specifically tasked with overseeing the regulation and management of pesticide use and ensuring that such usage does not adversely affect the environment, including groundwater resources. The monitoring of groundwater is crucial because pesticides can leach into the water supply and pose risks to both human health and the ecosystem.

Groundwater monitoring involves regular testing and analysis to detect harmful substances, including pesticides, thus helping to safeguard water quality. The Pesticide section's responsibility aligns with the goal of preventing contamination and ensuring safe agricultural practices.

The other sections listed do not focus specifically on pesticide-related groundwater issues. The Clean Water section generally deals with broader water quality issues rather than specifically targeting pesticides. The Groundwater section may oversee general policies and practices surrounding groundwater management but does not specifically focus on pesticides. The Licensing section typically handles the regulation of business permits and licenses related to pesticide application rather than monitoring contamination. Therefore, the Pesticide section is the entity directly involved in monitoring for pesticide contamination in Delaware's groundwater.