Which of the following is a preflight step for a galley service cart?

The completion of a preflight check for a galley service cart is essential to ensure safety and efficiency during service. Ensuring that all latches are secure is a critical step because it prevents any accidental openings during transit, which could lead to spills, injuries, or disruptions while the aircraft is in operation. This step contributes to maintaining the integrity of the cart's contents, ensuring that everything remains in place and is safely secured until needed.

Other choices, while they may seem relevant, do not align with the critical preflight checks necessary for galley service carts. For example, although it may be practical for the cart to be empty before service, the requirement does not directly relate to whether the cart can operate safely or effectively in transit. Likewise, the brake pedal not being set would imply the cart could roll away, which is contrary to ensuring its safe positioning. Lastly, if the cart is positioned in the aisle, that could obstruct movement rather than facilitate it; therefore, it's not a standard preflight step. Ensuring secure latches stands out as both a safety measure and a practical one, making it the most appropriate choice.