Which of the following is a responsibility of the Pilot-in-Command?

The responsibility of the Pilot-in-Command (PIC) encompasses a broad range of safety and operational duties, with one of the most critical being the assurance of operational safety of the aircraft. This includes overseeing the safety of the flight from departure to arrival, ensuring that all operations comply with aviation regulations, and making final decisions regarding the aircraft's safety during all phases of flight. The PIC must evaluate factors such as weather conditions, aircraft performance, air traffic, and any abnormal situations that arise, taking appropriate actions to mitigate risks.

Although monitoring air traffic, filing flight plans, and maintaining the airworthiness of passenger seats are also important, they do not encapsulate the overarching responsibility for the safety and decision-making authority that the PIC holds. The PIC must prioritize safety in every aspect of the flight operation, making option B the most accurate representation of their core responsibility.