Given the task definition and input, reply with output. 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'.

Sentence 1: I was playing a game of 5 minute speed chess. Sentence 2: My rating was 1300 and my opponent's was 1175. Sentence 3: My opponent was winning on material advantage. Sentence 4: Suddenly under time pressure he started making mistakes. Sentence 5: He lost on time in the end. Choices: a. Fate. b. Speed Chess Choke.
b