Which retail innovation, first introduced in 1916, revolutionized shopping by allowing customers to select their own items without clerk assistance?

The history of retail has been shaped by revolutionary innovations that transformed how we shop. From the earliest marketplaces to today's digital experiences, certain inventions stand out as game-changers. This poll tests your knowledge about one such pivotal innovation that fundamentally altered the retail landscape and consumer behavior in the early 20th century. Do you know which revolutionary retail concept first emerged to change shopping forever?

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Self-service grocery store (Piggly Wiggly)
Department store with multiple floors (Macy's)
Mail-order catalog shopping (Montgomery Ward)
Installment payment plans (Sears)