What precaution should be taken while loading materials onto a commercial vehicle?

Distributing the weight evenly across the vehicle is vital for maintaining stability and control while driving. An uneven load can cause the vehicle to tip or sway, particularly during turns or sudden maneuvers, leading to unsafe driving conditions. Proper weight distribution also ensures that the load does not exceed the vehicle's weight limits, which can affect braking, handling, and overall safety.

When the weight is spread evenly, it enhances the effectiveness of the vehicle's suspension system and promotes better tire contact with the road, reducing wear and improving traction. This practice also minimizes the risk of cargo shifting during transit, which can further impact vehicle stability.

In the context of the other options, loading all materials in the front could lead to a front-heavy vehicle, making the rear end lighter and thereby increasing the risk of losing control. Using only lightweight materials fails to address the importance of maintaining a balanced load, while stacking items as high as possible can raise the center of gravity, making tipping more likely.