ICS establishes lines of authority and reporting relationships that are described as _____________ and _____________.

The correct response highlights that ICS establishes lines of authority and reporting relationships described as supervisory and formal. In the context of the Incident Command System, "supervisory" refers to the hierarchical structure where each level of authority has a clear supervisor overseeing operations and personnel at lower levels. This system ensures accountability and clarity in roles, enabling effective communication and operation during incidents.

"Formal" emphasizes the established procedures and protocols that define these lines of authority. In a formally structured system like ICS, the processes and responsibilities are clearly outlined, ensuring that everyone involved understands their roles and who they report to. This formal structure is fundamental for effective management and coordination during complex incidents.

The other options do not accurately represent the intent and structure of ICS. For example, the term "informal" does not align with the need for clearly defined authority and accountability, which are vital in emergency management contexts. Similarly, terms such as "task" and "operational" focus more on the activities performed rather than the structured relationships between personnel and levels of authority.