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: I was walking along the sidewalk. Sentence 2: I saw a wallet on the ground. Sentence 3: I picked it up. Sentence 4: There was a driving license in it. Sentence 5: I mailed the wallet to the address on the license. Choices: a. Paying it forward. b. Wallet.

b