Which design innovation was specifically introduced to address needlestick injuries in medical settings?

Modern medical devices have undergone significant design transformations to improve patient outcomes and user experience. From ergonomic considerations to safety features, product design in medicine balances functionality with usability. This trivia question explores a notable design innovation that revolutionized a common medical device used by healthcare professionals worldwide.

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

Retractable safety syringes that automatically shield the needle after use
Color-coded needle hubs to indicate different gauge sizes
Transparent barrels to allow visualization of medication
Luer-lock connections for secure attachment to IV lines