Which statement accurately reflects the operational aspect of a lead-lag configuration?

In a lead-lag configuration, the lag unit serves an important role to ensure reliability and continuity of operations. The statement indicating that the lag unit can be preemptively activated during normal operations accurately reflects this setup. In practice, the lag unit is often kept in a standby mode but can be activated when the lead unit approaches its capacity limits or when maintenance is required on the lead unit. This proactive approach allows for smooth transitions and prevents system overloads, contributing to enhanced operational efficiency and stability.

The other options highlight misunderstandings about lead-lag configurations. For instance, stating that the lead unit operates independently without any backups overlooks the collaborative nature of these systems. Describing the lead unit as being used only during emergencies suggests a reactive rather than proactive operational strategy. Lastly, the idea that both units are always active simultaneously does not align with the intended design of lead-lag systems, which typically involve one unit functioning as the primary (lead) while the other (lag) remains on standby until needed.