Detailed Instructions: In this task, you're given the title of a five-sentence story, the first four sentences, and two options for the fifth sentence as a and b. Your job is to pick the sentence option that seamlessly connects with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes more sense.
Q: Title: Overweight. Sentence 1: Hayden was 50 pounds overweight. Sentence 2: He decided one day to go on a diet. Sentence 3: On the first day of his diet, he went walking for 3 hours. Sentence 4: He was extremely tired when he was done walking. Choices: a. She agreed that the song fit them perfectly. b. But, he knew this was the start of a healthy lifestyle.
A:
b