When the **vehicle's wheels are unbalanced**, there is an increase in **vibrations** in the vehicle. This occurs because the balance of the wheels is crucial for them to rotate correctly and support the weight and load of the vehicle. If the wheels lose this balance, for example, due to a tire change or the rims losing their counterweights, the vehicle will start to vibrate more than normal.

These vibrations can affect the **stability of the steering**, making it more difficult for the driver to maintain control of the vehicle. Additionally, a suspension system in poor condition, which is responsible for maintaining contact between the tires and the road, can exacerbate this problem, as the vehicle would lose stability, especially in curves or with wind.

Therefore, when the wheels are unbalanced, it is common to experience **vibrations** and a **destabilization of the steering**, which confirms that the correct answer is the first option.