What can be the consequence of wrongly setting the headlamp levelling control?

You answered correctly because if the headlamp leveling control is set incorrectly, two main problems can occur. First, if the headlights are aimed too high, they can dazzle or blind oncoming drivers, creating a safety hazard. Second, if the headlights are aimed too low, their range will be reduced, making it harder for you to see the road ahead at night or in poor visibility conditions. The third option about reducing the life-cycle of the bulb is not related to the leveling control setting but rather to bulb quality and usage. Correct headlamp adjustment ensures both your safety and that of others on the road.