Question

never exactly said, but i knew why the beach was special to her. it was the place whe shed met my dad.
as we got closer to montauk, she seemed to grow younger, years of worry and work disappearing from her face. her eyes turned the color of the sea.
we got there at sunset, opened all the cabins windows, and went through our usual cleaning routine.
we walked on the beach, fed blue corn chips to the seagulls, and munched on blue jelly beans, blue saltwater taffy, and all the other free samples my mom had brought from work.
i guess i should explain the blue food.
see, gabe had once told my mom there was no such thing. they had this fight, which seemed like a really small thing at the time. but ever since, my mom went out of her way to eat blue. she baked blue birthday cakes. she mixed blueberry smoothies. she bought blue - corn tortilla chips and brought home blue candy from the shop. this—along with keeping her maiden name, jackson, rather than calling herself mrs. ugliano—was proof that she wasnt totally suckered by gabe. she did have a rebellious streak, like me.
from rick riordan, the lightning thief. copyright 2005 by rick riordan
how does percys mom most likely feel when at the cabin?
she feels overwhelmed with emotion.
she feels a sense of comfort and ease.
she feels frustrated by its shabby condition.

Explanation:

The text states that as they approached Montauk (where the cabin is), years of worry and work disappeared from her face, and she seemed to grow younger. They carried out calm, familiar routines like cleaning and enjoying the beach with blue foods, which are a small, joyful act of rebellion for her. This all points to a relaxed, comfortable state rather than being overwhelmed or frustrated.

Answer:

She feels a sense of comfort and ease.