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: Moonlighting. Sentence 1: Mary worked hard as a nurse at the hospital. Sentence 2: To make extra money she worked a second job. Sentence 3: Mary was often tired because of her long work hours. Sentence 4: At the hospital she almost made a dangerous error due to fatigue. Choices: a. Mary decided that it would be best to quit her second job. b. Marty promised herself that she'd never forget the sunscreen again.
A:
a