Final answer:
NOTAMs are advisories or warnings that provide essential information for flight safety, such as potential hazards and changes to aeronautical facilities. They are critical for aviators to ensure safe flight operations and are not meant for routine procedures, permanent regulations, or merely local airport information.
Step-by-step explanation:
Notices to Airmen (NOTAMs) are time-critical aeronautical information relevant to personnel involved in flight operations. The purpose of NOTAMs is to inform aviators of information that is essential for safe flight. This information typically includes advice or warnings about circumstances that could affect flight safety, such as construction on airfields, changes to aeronautical facilities, services, procedures, hazards, or the establishment of temporary airspace restrictions.
The correct answer to the question is: a) Advisories or warnings. NOTAMs are not meant to convey routine procedures, they are not a means for disseminating permanent regulations, and they are not solely for local airport information; they can be relevant to aviation on a much broader scale, potentially affecting international flight operations.