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: Kim wanted to surprise her boyfriend. Sentence 2: She knew he never got a real birthday party. Sentence 3: She called all his friends and planned one out. Sentence 4: Kim's boyfriend had no clue. Sentence 5: He was extremely happy and surprised. Choices: a. Surprise Party. b. Speed Chess.

a