Final answer:
UV radiation is an extrinsic factor that affects the skin by causing premature wrinkling, pigmentation changes, and an increased risk of skin cancer.
Step-by-step explanation:
One example of something which has an extrinsic effect on the skin is B) UV radiation. Ultraviolet (UV) radiation from the sun is an environmental factor that significantly affects the skin by damaging collagen fibers, leading to photo-aging, which includes premature wrinkling and changes in pigmentation.
Exposure to UV light can also increase the risk of skin cancers and cause changes such as sunburns which are signs of immediate damage. The genetic expression can be modified by UV radiation through epigenetic changes that affect the accessibility and transcription of DNA.