In this task, you're given five sentences, numbered 1 through 5, and two options a and b for possible titles for the story. Your job is to choose the title that better fits the story. Indicate your choice by 'a' or 'b'.

Example Input: Sentence 1: Ethan's friends challenged him to drink 2 liters of cola in an hour. Sentence 2: They pooled their funds and offered him twenty dollars. Sentence 3: Ethan accepted the challenge. Sentence 4: He struggled, but he managed to drink all the cola on time! Sentence 5: However, that night Ethan had a terrible stomach ache! Choices: a. Challenge. b. Slow in understanding.
Example Output: a

Example Input: Sentence 1: A trapeze artist stood on the skyscraper. Sentence 2: He didn't look down. Sentence 3: He looks ahead. Sentence 4: He steps out onto the rope. Sentence 5: He crosses it very easily. Choices: a. Gon Wants to Win. b. Walk the Line.
Example Output: b

Example Input: Sentence 1: After the hurricane came through the Jones' were in a bad spot. Sentence 2: Their house had taken a lot of damage. Sentence 3: They had to call in lots of people to help fix it. Sentence 4: They restored a lot of the house and rebuilt what they couldn't fix. Sentence 5: After a lot of time and work the Jones' house was finally fixed. Choices: a. Promotion. b. Restoration.
Example Output:
b