Final answer:
The capability available only with enhanced SLAs is the ability to pause an SLA, which adds flexibility to SLA management by allowing pauses during specific criteria, unlike basic SLAs.
Step-by-step explanation:
The question concerns the capabilities that are exclusively available when using enhanced Service Level Agreements (SLAs). Among the choices presented, the feature that is only possible with enhanced SLAs is to pause an SLA. This is because the traditional basic SLAs do not offer this functionality, whereas enhanced SLAs provide a more flexible and dynamic approach, allowing SLAs to be paused during the time in which the criteria for the pause are met. Being able to pause an SLA can be useful for situations where waiting for customer feedback or other events that should not count against the service time.
Other options like using security roles for SLA creation, tracking Key Performance Indicators (KPIs), and defining failure actions are available in both basic and enhanced SLAs but with the enhanced version providing more functionality and flexibility.