Which of the following is one of the criteria for notifying NTSB?

Notifying the National Transportation Safety Board (NTSB) is required when there is a flight control system malfunction because this situation poses a significant safety risk to flight operations. Flight control systems are critical components that directly affect the aircraft's ability to maneuver and maintain safe flight. When a malfunction occurs, it can potentially lead to serious incidents or accidents. Therefore, such occurrences must be reported to ensure appropriate investigations can take place, and corrective measures can be implemented to enhance aviation safety.

In contrast, minor accidents may not always meet the threshold for mandatory reporting, as defined by NTSB criteria. Routine inspections are standard operating procedures and do not typically involve reporting to the NTSB. Additionally, administrative errors do not usually result in immediate safety hazards that necessitate NTSB involvement. The focus of NTSB notifications is on incidents that could have severe implications for safety in aviation.