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: Scientists have been working at Los Alamos on a new bomb. Sentence 2: The theory was easy to develop. Sentence 3: They decided on a final design. Sentence 4: They determined what material would be needed. Sentence 5: Now they wait on the material for their gadget to be produced. Choices: a. Weak Step. b. The Design is Final..

b