Which of the following actions is not part of a flight attendant's responsibilities during turbulence?

During turbulence, flight attendants focus on ensuring the safety and comfort of passengers. Securing the cabin, providing reassurance, and ensuring seat belts are fastened are all critical components of a flight attendant's responsibilities during such conditions.

Offering food and beverage service, on the other hand, is not appropriate during turbulence. This is because the safety of passengers takes priority, and serving food and drinks can be risky when the aircraft is experiencing instability. Items being served could become projectiles, and the movement of the aircraft can create an unsafe environment for both the crew and passengers.

Thus, the correct action that is not part of a flight attendant's responsibilities during turbulence involves food and beverage service, as safety protocols dictate that service should be halted until the turbulence subsides and the cabin environment is stable.