Storing materials on racks and shelves is beneficial because it:

Storing materials on racks and shelves is beneficial primarily because it minimizes the need to bend down to lift items from the floor level. This practice promotes better ergonomics and reduces the risk of strain or injury while handling materials. When items are elevated on racks or shelves, workers can access them at a more comfortable height, leading to safer lifting techniques and decreasing the potential for musculoskeletal disorders.

Additionally, the use of racks and shelves aids in organization, which can enhance overall workplace efficiency. While cleanliness and compliance with OSHA regulations are important considerations, the primary benefit highlighted in the correct choice focuses specifically on improving safety and ease of access for workers.