Correct answer: A. It would have no effect.
It might be difficult to start a car with a weak battery, but once the engine is running, it makes no difference. If the battery fails to charge or maintain its full charge seek advice from a competent person.
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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