What does higher levels of melanin provide against UVA radiation?

Higher levels of melanin in the skin provide greater protection against UVA radiation due to its role as a natural photoprotective agent. Melanin absorbs harmful ultraviolet (UV) rays, reducing their ability to penetrate the skin and cause damage to cellular DNA, which can lead to skin cancer and other skin-related issues. This protective function of melanin is especially crucial in populations living in areas with higher ultraviolet radiation exposure, as it helps to mitigate the risks associated with sun exposure.

In contrast, options that suggest benefits such as better heat retention, improved skin moisture, or more vitamin D production do not directly relate to the protective qualities of melanin against UVA radiation. Heat retention and moisture retention are influenced by other factors, and while vitamin D production is important, it primarily occurs in response to UVB radiation rather than being a protective measure against UVA. Thus, the significant role of melanin in protection against UV radiation is what makes the correct choice evident.