Which of the following BEST illustrates someone who exhibited perseverance in the face of struggle?

A.
Sally needed a good grade on her calculus exam in order to graduate at the top of her class, but because she knows she is not good in math, she decided not to study and took a lower grade instead.
B.
Bobby decided that he was going to finish his summer job despite the fact his boss dislikes him, but he decides after a few weeks that he simply cannot work there the whole summer and quits.
C.
After spraining an ankle during a marathon, Jean continued to the finish line since she decided prior to the race that nothing would keep her from finishing.
D.
Since Lance was behind the leader of the bike race with only ten miles left, he decided to withdraw from the competition and race again next year.