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: 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. Sentence 5: Marcus was happy to have the right clothes for the event. Choices: a. Marcus Buys Khakis. b. Marcus Works.
Example output: a
Example explanation: Marcus's reasons for buying khakis is established, followed by his purchase of them and reaction.
Q: Sentence 1: Becky just had a baby. Sentence 2: Becky's husband left her for a younger woman when she was pregnant. Sentence 3: Becky tried to sleep for a few minutes but the baby started crying. Sentence 4: She changed the baby's diaper and rocked it to sleep. Sentence 5: Becky laid down again hoping for a few minutes of rest. Choices: a. Building Blocks. b. Diaper Duty.
A:
b