Answer: Lack of melanin in the skin.
Explanation: The amount of melanin in your body is determined genetically. Some people dont produce enough melanin to protect their skin well. Eventually the UV causes the skin to burn, causing redness, swelling and pain.
PLEASE RATE 5 STARS AND VOTE AS BRAINLIEST:)
(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)(^o^)