You buy a car and find that the spare tyre is smooth; the tread is only just visible. If you get a puncture will it be legal to drive the car with a smooth spare tyre?

• A. Yes, if the tyre is correctly inflated and the side walls of the tyre are in good condition.
• B. No, it's illegal to drive a car with a smooth tyre even if it is the spare.
  Explanation:

  "In the event that you have to use the spare because of a puncture, your vehicle will become dangerous to drive."
• C. Yes, but you must get the puncture fixed within 24 hours.