Correct answer: D. Use the mirror, signal and move into the right-hand lane when a suitable gap appears in the traffic in that lane.
Any time you change lanes, you should use the Mirror–Signal–Mirror (blind spots)–Manoeuvre routine. Check your mirrors, signal your intention, check your mirrors again (and your blind spots), and when a suitable gap becomes available manoeuvre the vehicle into the next lane, giving way to traffic already in that lane.
This is an official-style question from the Safe and Responsible Driving topic of the Ireland driver theory test (Cat. B). Practise all 804 questions free on iTest.ie — with timed mock exams, automatic mistake tracking and progress sync across devices.
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