What should be noted when changing a tyre using a car jack?

Your answer is correct because when changing a tyre with a car jack, it is essential to use the designated positioning points specified by the vehicle manufacturer to avoid damage and ensure stability. Additionally, the ground surface must be stable and skid-resistant to prevent the jack from slipping, which could cause the vehicle to fall. Placing the jack at the mid-point of the vehicle's length, as stated in the incorrect option, is not a general rule and may not provide safe support depending on the vehicle's design. Always follow the manufacturer's instructions and choose a firm, level surface for safety.