What type of ray is primarily responsible for causing burns on the skin?

The type of ray primarily responsible for causing burns on the skin is UVB. UVB rays are a part of the ultraviolet spectrum and have a shorter wavelength than UVA rays, which allows them to penetrate the outer layer of the skin more effectively. These rays are known for their ability to cause sunburns and are associated with direct damage to the DNA in skin cells, leading to the inflammatory response that results in redness, pain, and burning sensations.

In contrast, UVA rays penetrate deeper into the skin but are more associated with photoaging and long-term skin damage rather than immediate burns. UVC rays, while the most harmful in terms of potential skin damage, are mostly absorbed by the Earth's atmosphere and do not reach the skin under normal conditions. X-rays are a form of ionizing radiation used in medical imaging and do not primarily cause burns in the same context as ultraviolet rays. Therefore, UVB's specific role in causing skin burns makes it the correct answer to this question.