When you ask for the answer, you get the model's single most average take. When you ask for several genuinely different options, you get a spread — and your judgment does what it's best at: picking and combining.
The trick is forcing real variety. "Give me 5 headlines" produces five near-clones. "Give me 5 headlines using 5 different angles: urgency, curiosity, social proof, data, contrarian" produces five actually-different candidates. Name the axes of variation, then pick a winner and iterate on it alone.