Correct answer: C. 100 metres.
At night in good driving conditions the full headlights of a car will typically let you see 100 metres ahead. So, you should travel at a speed that allows you to stop within that distance.
This is an official-style question from the Safe and Responsible Driving topic of the Ireland driver theory test (Cat. B). Practise all 807 questions free on iTest.ie — with timed mock exams, automatic mistake tracking and progress sync across devices.
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