Which type of UV radiation accounts for 95% of the sun's rays during summer?

The type of UV radiation that accounts for 95% of the sun's rays during summer is UVA. UVA radiation has a longer wavelength than UVB and penetrates deeper into the skin, affecting the dermis and contributing to skin aging and the development of skin cancer. It is the most prevalent form of UV radiation reaching the Earth's surface, especially during the summer months when the sun is higher in the sky.

In contrast, UVB radiation, while responsible for causing sunburn and playing a key role in the production of vitamin D, accounts for a smaller percentage of the sun's rays compared to UVA during this time. UVC radiation is mostly absorbed by the Earth's atmosphere and does not reach the surface, making it irrelevant when discussing UV exposure from sunlight. UVD is not a recognized classification of UV radiation in this context, further solidifying the choice of UVA as the correct answer. Understanding the distinction between these types of UV radiation is crucial for making informed decisions about sun safety.