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.
Example: Title: Marcus Buys Khakis. Sentence 1: Marcus needed clothing for a business casual event. Sentence 2: All of his clothes were either too formal or too casual. Sentence 3: He decided to buy a pair of khakis. Sentence 4: The pair he bought fit him perfectly. Choices: a. Marcus was happy to have the right clothes for the event. b. He left in a huff for having his ideas mocked.
Example solution: a
Example explanation: Marcus is buying clothes for a business event and not presenting an idea.

Problem: Title: Heather sells lemonade. Sentence 1: Heather wants a new toy. Sentence 2: She asks her parents to buy it for her. Sentence 3: Her parents tell her she will have to work to earn it. Sentence 4: Heather sets up a lemonade stand. Choices: a. She can't wait for summer. b. She sells enough to buy her new toy.

Solution: b