Chair back support at the workplace helps reduce which problem?

Correct answer: Lower back and back strain

A chair back support is an ergonomic feature that helps keep the spine and lower back in a comfortable, stable position. When a person sits for a long time without support, the back muscles may become tired and the body may bend forward. Proper support can reduce unnecessary strain and help maintain a better sitting posture. It does not solve unrelated office or building problems.

Option A is correct because back support is designed to reduce lower-back discomfort and back strain. Options B, C, and D concern papers, rent, and wall height, so they have no direct connection with the purpose of chair design. Ergonomics connects workplace furniture with the safety, comfort, and health of the worker.