Office invention in 1951: Identify what Bette Nesmith Graham created. Full question: What office item was invented by Bette Nesmith Graham in 1951? Choose the correct option.

Given data

• Inventor: Bette Nesmith Graham.
• Year: 1951; domain: office supplies.

Concept / Approach
Liquid Paper (correction fluid) was created by Bette Nesmith Graham to cover typing errors, later commercialized as a widely used office product.

Option analysis
Correction fluid — Correct. Post-it Notes — 3M (Spencer Silver/Art Fry), 1970s. Photocopier — Chester Carlson (xerography), 1938/1940s commercialization. Stapler — 19th-century origins, not 1951.

Final Answer
Liquid Paper (correction fluid).