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 Input: Title: Balloons. Sentence 1: Carl was an old man who sold balloons. Sentence 2: One day, he met a young boy named Russell. Sentence 3: Russell wanted a balloon but couldn't afford one. Sentence 4: Carl was in a charitable mood. Choices: a. Bill then realized it was Saturday. b. He gave Russell two balloons for free.
Example Output: b

Example Input: Title: Cheap Thrills. Sentence 1: Sia didn't have any cash. Sentence 2: Her boyfriend had come over earlier. Sentence 3: They danced all through her house. Sentence 4: Sia was very happy. Choices: a. His car engine is blown up! b. She decided it was okay she didn't have money to go out.
Example Output: b

Example Input: Title: Great Friend. Sentence 1: I started college this year and met a new friend at orientation. Sentence 2: I accepted his friend request on Facebook, thinking nothing of it. Sentence 3: He went through my timeline liking photos from years ago. Sentence 4: Then he sent me a message asking to be my dirty little secret. Choices: a. He knows I have a boyfriend and that's why he started doing this. b. Now I've got to find some type of lock for my new room.
Example Output:
a