What is meant by a "sensitivity receptor" in terms of pesticide exposure?

A "sensitivity receptor" refers to individuals or ecosystems that are particularly vulnerable to pesticide exposure. This term encompasses various living organisms and environmental systems that may experience adverse effects from pesticide usage due to heightened sensitivity.

For example, certain species of animals, such as fish or amphibians, may be more impacted by pesticides because of their physiological traits, while specific ecosystems like wetlands may be more easily disrupted by chemical runoff. Understanding which receptors are sensitive helps in assessing risk and implementing protective measures to minimize pesticide-related harm.

In contrast, the other options do not accurately define the concept of a sensitivity receptor. Being immune to pesticides would imply a lack of susceptibility, which contradicts the definition of sensitivity. Focusing solely on humans or plants limits the broader understanding of ecological impacts, as sensitivity receptors can include a wide range of organisms and systems within the environment. Thus, option B provides the most comprehensive and accurate representation of what a sensitivity receptor entails in the context of pesticide exposure.