What must the No4 check during their PDIs?

The correct choice emphasizes the importance of conducting thorough cabin checks during the Pre-Departure Inspection (PDI) specifically at rows 1-11. These rows are significant as they often include priority areas such as the first-class section or rows closest to the exits, which are crucial for safety and service. Ensuring that the cabin is secure and ready for passengers in these rows can significantly enhance safety and efficiency before takeoff. This involves checking for any potential hazards, verifying that safety equipment is in place, and ensuring that the cabin is tidy and ready for boarding.

While assigned door checks, galley checks, and evacuation slide checks are also components of pre-flight preparations and contribute to the overall safety and service quality, the specific focus on cabin checks at rows 1-11 underlines the urgent need to prioritize areas that may need immediate attention as the flight prepares for departure. This highlights the No4's responsibility in ensuring that these key customer service areas are addressed during PDIs for optimal passenger experience and safety protocols.