Final answer:
Loss in skin pigmentation, as occurs in vitiligo, is not an effect of UV radiation, whereas increased melanin production, DNA damage, aging of skin due to reduced elastic fibers, and production of vitamin D are.option a is correct.
Step-by-step explanation:
Effects of Ultraviolet Radiation
Ultraviolet (UV) radiation has various effects on the skin. Increased production of melanin by melanocytes is a protective response to UV exposure, helping to protect the skin from damage by absorbing and dissipating UV radiation. Damage to DNA in epidermal cells can occur, potentially leading to skin cancer. UV radiation can also reduce the amounts of elastic fibers in the dermis, contributing to skin aging and wrinkle formation.
However, not all effects attributed to UV radiation are accurate. Loss in skin pigmentation, as seen in conditions like vitiligo, is not a result of UV radiation but rather is caused by the body's immune system attacking and destroying melanocytes. UV exposure can indeed cause chromosomal damage in germinative cells or melanocytes, which may lead to mutations and cancer. Furthermore, UV radiation stimulates the production of cholecalciferol (vitamin D3) within epidermal cells, which is essential for various body functions, including bone health.