Which retail innovation, introduced in 1937, fundamentally transformed shopping by allowing customers to select their own merchandise without clerk assistance?

Before e-commerce dominated our shopping experiences, physical retail underwent numerous innovations that revolutionized how we shop. Some retail innovations were so transformative that they fundamentally changed consumer behavior and set the foundation for modern shopping experiences. Test your knowledge of retail history with this challenging question about a game-changing innovation from the past century.

This is a live public trivia poll on AIPolls.Net. Vote and see real-time results.

Shopping carts (invented by Sylvan Goldman for his Humpty Dumpty supermarket chain)
Barcode scanners (introduced by Marsh Supermarket but not until 1974)
Self-checkout kiosks (first implemented by David R. Humble in the 1980s)
Electronic point-of-sale systems (widespread adoption didn't begin until the 1970s)