A change to any of the following inputs will affect the balance of the vehicle, except:

The balance of a vehicle, which refers to how weight is distributed and affects its handling and stability, is influenced significantly by how the vehicle is driven through steering, acceleration, and braking.

When steering inputs are made, the distribution of weight changes from side to side, which can affect the vehicle's balance during turns. Similarly, acceleration shifts the weight toward the rear of the vehicle, while braking shifts it toward the front, both of which can impact how stable the vehicle feels and how it handles.

On the other hand, the addition or movement of passengers affects the vehicle's overall weight but does not inherently change the dynamic balance of the vehicle in the same way the other inputs do. While having passengers in a vehicle can affect its performance and handling due to changes in total weight, the question specifically asks about changes to inputs that affect balance during driving maneuvers. Since the actions of steering, accelerating, and braking are active inputs, they directly influence the immediate balance of the vehicle, whereas the presence of passengers is more of a passive factor. Thus, the correct choice is that changing the number of passengers does not directly affect balance in the context of dynamic driving inputs.