You will be given a definition of a task first, then some input of the task.
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 does not connect with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes less sense.

Title: Losing Weight. Sentence 1: Tina had gained fifty pounds over the last year. Sentence 2: She was determined to get into shape. Sentence 3: Tina started to eat right. Sentence 4: Her friends got Tina to join a gym. Choices: a. Tina lost all the weight she had gained. b. Lisa couldn't get the stain out her dress.
Output:
b