Ace the Certified in Public Health (CPH) Exam 2025 – Launch Your Health Hero Journey!

The correct answer is grounded in the role of the ozone layer as a protective shield for the Earth. The ozone layer absorbs the majority of the sun's harmful ultraviolet (UV) radiation. When the ozone layer is degraded, whether through human-made chemicals like chlorofluorocarbons (CFCs) or other environmental factors, more UV radiation can penetrate the atmosphere and reach the surface of the Earth.

Increased exposure to UV radiation is directly linked to several health issues. One of the most significant effects is an increase in skin cancers, particularly malignant melanoma and basal cell carcinoma. UV exposure can also lead to cataract formation and other eye diseases. Additionally, heightened UV radiation can suppress the immune system, reducing the body’s ability to fight off certain illnesses and infections.

Thus, understanding the connection between ozone depletion and increased UV radiation highlights the critical importance of the ozone layer in maintaining public health.