How many flight attendants are required for a flight with 150 passenger seats?

For a flight with 150 passenger seats, the appropriate number of flight attendants determined by regulatory guidelines is based on the need to ensure safety and efficient service. Generally, the standard ratio is one flight attendant for every 50 passenger seats. In this case, with 150 seats, the calculation would suggest that at least three flight attendants are necessary, which aligns with option B.

However, airlines often opt for additional flight attendants based on various factors such as the length of the flight, service requirements, and operational considerations. Thus, having four flight attendants not only meets regulatory standards but also enhances the level of service, safety, and passenger comfort on board. This is why four flight attendants is a correct and preferred response for a flight of this size, allowing for more effective crew management and the ability to address passenger needs more efficiently.