Does UVB penetrate the skin more deeply than UVA?

The assertion that UVB does not penetrate the skin more deeply than UVA is based on the fundamental characteristics of these types of ultraviolet radiation. UVA rays penetrate the skin more extensively, reaching deeper layers, such as the dermis. In contrast, UVB rays primarily affect the outermost layers of the skin, particularly the epidermis, where they play a significant role in causing sunburn and damaging the skin.

Understanding the differences in penetration is essential for evaluating the effects of UV radiation on skin health. UVA is associated with skin aging and some forms of skin cancer due to its depth of penetration and its ability to generate reactive oxygen species that can damage cellular DNA. Meanwhile, UVB's primary role is in causing erythema (sunburn) and is more effective at inducing the production of vitamin D in the skin.

The other options imply variations in penetration depth based on conditions or individual factors, which do not negate the established understanding that UVA penetrates deeper than UVB. Therefore, the choice affirming that UVB does not penetrate the skin more deeply than UVA aligns with the scientific consensus regarding the behavior of these ultraviolet rays.