Under which circumstances should a synthetic sling be discarded?

The correct choice highlights the importance of inspecting synthetic slings for visible signs of damage that compromise their integrity and safety. Synthetic slings are designed to have high strength and flexibility, but exposure to environmental factors such as cuts, burns, or UV damage can significantly weaken them. If any of these conditions are present, the ability of the sling to safely carry loads is compromised, which poses a risk during lifting operations. Therefore, slings exhibiting such damage should be discarded to ensure the safety of all personnel involved in the lifting process.

The other circumstances listed, such as being overly stretched, used in wet conditions, or discolored, do not inherently warrant immediate disposal unless they are accompanied by visible damage or performance issues. While these factors could indicate wear and may affect the sling's lifespan, they do not automatically necessitate discarding the sling like physical damage does.