1. The problem is to choose the best topic sentence that introduces a paragraph containing the given details about animation techniques. 2. The details describe how creators of animated films study real-life examples (live action footage, real runners, scuba diving) to create realistic animations. 3. The formula for choosing a topic sentence is to find one that broadly and accurately summarizes the main idea of the details. 4. The first option focuses only on Finding Nemo and water animation, which is too narrow. 5. The second option talks about advancements in computer technology, which is unrelated to the details given. 6. The third option states that makers of animated movies rely on studying real-world examples to create convincing animation, which matches all the details. 7. Therefore, the best topic sentence is: "The makers of animated movies often rely on the study of real-world examples to create convincing animation."