What illness has been linked to exposure to PCBs?

The correct answer is cancer, as exposure to polychlorinated biphenyls (PCBs) has been linked to an increased risk of developing certain types of cancer. PCBs are a group of man-made organic chemicals that were widely used in electrical equipment and other industrial applications until their production was banned in many countries due to health concerns. Long-term exposure to PCBs has been associated with various types of cancer, including liver and skin cancer, as well as a range of other adverse health effects.

The other options involve health issues that are not primarily connected to PCB exposure. Respiratory diseases, asthma, and heart disease have various causes and risk factors that tend to differ significantly from those associated specifically with PCB exposure. While there may be some overlap in environmental health contexts, the most direct and widely studied link remains between PCBs and cancer. This connection is supported by epidemiological studies demonstrating elevated cancer rates among populations with significant PCB exposure.