The nurse recognizes which of the following population groups is at highest risk for melanoma? ? A. Adults older than 35 ? B. Senior citizens who have had repeated exposure to the sun ? C. Employees of a chemical plant ? D. 22-year-olds who tan in tanning beds three times a week

Melanoma is a type of skin cancer that develops in the melanocytes, the cells responsible for producing melanin, which gives color to the skin, hair, and eyes. The primary risk factor for melanoma is exposure to ultraviolet (UV) radiation, which can come from the sun's rays or artificial sources like tanning beds. People with fair skin, a family history of melanoma, and those with numerous moles are also at a higher risk.

Now, let's examine each population group and assess their risk of developing melanoma based on the known risk factors: Option A: Adults older than 35: People aged 35 and older are at a higher risk of melanoma, but it is not the primary risk factor. Option B: Senior citizens who have had repeated exposure to the sun: This population group has two risk factors: older age and repeated sun exposure, making them more likely to develop melanoma. Option C: Employees of a chemical plant: Working in a chemical plant may expose workers to some hazardous substances, but it doesn't directly relate to the development of melanoma. Option D: 22-year-olds who tan in tanning beds three times a week: This group is young, but they are frequently exposed to artificial UV radiation, which is a major risk factor for melanoma.

Based on the analysis of each option, it is evident that the 22-year-olds who tan in tanning beds three times a week (Option D) are at the highest risk for melanoma due to their frequent exposure to artificial UV radiation, which is a significant risk factor in melanoma development. Thus, the correct answer is: ? D. 22-year-olds who tan in tanning beds three times a week.