Definition: 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'.
Input: Sentence 1: Norma and Robert had only planned to have three children. Sentence 2: After that either she would get a tubal ligation or he a vasectomy. Sentence 3: But they neither or them ever got around to it after the third child. Sentence 4: One day Norma had a suspicion confirmed by a positive pregnancy test. Sentence 5: An ultrasound confirmed not only was she pregnant but it was twins! Choices: a. Old Currency. b. Plus.

b