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: Trading homework. Sentence 1: Janet had too much homework to do that day. Sentence 2: She asked her brother to do all her math equations for her. Sentence 3: He accepted if she'd write an essay for his English class. Sentence 4: They agreed and did as promised. Choices: a. They were very lucky as no one realized what had happened. b. And the driver seeing her despair, stopped the bus to let her in.

Solution: a