What adjustment should be made to the backrest to prevent goods from slipping when raised?

The correct adjustment to prevent goods from slipping when raised is to lean the backrest backward. This position helps create a more secure angle against the load being lifted, thereby providing a more stable environment for the materials. When the backrest leans backward, it minimizes the risk of the load tipping or shifting, particularly during movement or turns.

In contrast, leaning forward would not provide the same level of support and could potentially allow items to slide off the back of the forklift. If the backrest remains upright, it may not adequately prevent the load from moving, especially if items are not snugly packed. Removing the backrest entirely would likely create a significant safety hazard, as there would be no support to keep the load secure while being transported.