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 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: Choosing a Ring. Sentence 1: Dan wanted to propose to Cathy but did not have the ring yet. Sentence 2: He asked her about the types of rings that she favored. Sentence 3: Dan shopped online and in stores, looking for the perfect ring. Sentence 4: At the last store, a sparkling diamond attracted his attention. Choices: a. Dan purchased the ring, proposed to Cathy and is now engaged. b. They were able to repair his computer for a fee of $50.
Output:
a