Situation Jen Has Fair Skin,and Both Her Mother and Her Aunt

Situation
Jen has fair skin,and both her mother and her aunt have been treated for skin cancer.This coming weekend,Jen and her friends are planning an all-day outdoor hike near a high-mountain lake;she expects there will be a mix of sun and shade on the trail and at the lakeshore beach.She is looking forward to the hike,but she wants to avoid getting a sunburn or any sun damage.
-The group is tentatively planning to have a noon lunch on the lakeshore beach.To protect her skin at lunchtime,Jen's best strategy would be to

A) change the plan so that the group has lunch at a shaded picnic table and dinner on the beach.
B) eat under a beach umbrella to protect herself from the sun's rays.
C) not worry,since the high altitude of the lake means the sun's rays are less intense.
D) go swimming for most of the lunch break because the water will protect her from UV rays.