Which of the following is not a method of mechanical handling?

The correct choice identifies "trolley" as not a method of mechanical handling in the context typically addressed in forklift operation. Mechanical handling generally refers to equipment and methods that use machinery or technology to move, lift, or transport loads without the direct manual effort of an operator.

Conveyor belts, forklifts, and other devices like cranes are clearly classified as mechanical handling systems because they involve powered or mechanized equipment to facilitate the movement of goods. For instance, a forklift is designed specifically for lifting and transporting pallets and other heavy materials with ease, greatly reducing the need for manual labor. Conveyor belts automate the movement of items from one point to another, enhancing efficiency in warehouses and production lines.

In contrast, hand lifting refers to manual methods of handling where an individual physically lifts and moves items without the assistance of machinery, making it a non-mechanical method. A trolley, while it may assist in transporting items, does not fit into the category of mechanical handling because it typically relies on human effort for movement and does not involve powered systems inherent to mechanical handling devices. Thus, recognizing that the question focuses on mechanical handling methods underscores why the trolley is the correct choice for this inquiry.