57.
The answer is: A
Explanation
The correct option is A: Eric Ries.
Eric Ries is the author of "The Lean Startup," a book that introduces a systematic and scientific approach for creating and managing successful startups. In the book, Ries emphasizes the importance of continuous innovation and validated learning through the build-measure-learn feedback loop. His methodologies are designed to help entrepreneurs and startup founders develop products that meet market needs while minimizing wasted efforts and resources.