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: Gareth loved animals. Sentence 2: His favourite animal was the Rhino. Sentence 3: He felt so sad that they were going extinct. Sentence 4: Gareth decided to move to Africa to help Rhinos. Sentence 5: He adopted a Rhino called Mahimba who became his best friend. Choices: a. Saving the rhinos. b. Big Premier.

a