Lifting equipment must be operated within its __________.

The correct answer is the Working Load Limit (WLL) because it specifically defines the maximum weight that lifting equipment is designed to handle safely under normal conditions. Adhering to the WLL is crucial to prevent equipment failure, accidents, or injuries. Ensuring that the load does not exceed WLL ensures that the lifting equipment operates within safe parameters established by the manufacturer.

While other factors like safety margins, manufacturer guidelines, and operational capacities are relevant to the safe use of lifting equipment, the WLL provides the precise measurement of the maximum load limit. This makes it the most critical indicator to follow when operating lifting equipment, as it directly relates to the physical limitations of the equipment's design and material strength.