Correct answer: A. It lubricates the engine.
The purpose of engine oil is to lubricate and cool the moving parts of the engine. Refer to the vehicle handbook for further information and guidance.
This is an official-style question from the Technical Matters 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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