How long does an MOT last?

Answer: B — one year

An MOT lasts for one year, as this is the legal requirement for all vehicles before they are due for another test. Option A (6 months) is incorrect because this is only the period for a new car's first MOT. Option C (two years) is incorrect as this rule only applies to newer vehicles with low mileage. Option D (until the vehicle is sold) is incorrect because an MOT expires after one year, regardless of whether the vehicle is sold or not.