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.

Title: Fun on the swings. Sentence 1: Rene loved the swings. Sentence 2: She didn't think she was too old to use them. Sentence 3: Rene went very high. Sentence 4: At the end she jumped off. Choices: a. She had much fun. b. They opened the pool when he was done.
a