Final answer:
If a placarded vehicle gets a leaking or overheated tire while on the road, the driver must stop in a safe location and contact a professional for assistance or replace the tire if necessary.
Step-by-step explanation:
If a placarded vehicle gets a leaking or overheated tire while on the road, the driver must take the necessary actions to ensure their safety and the safety of others. The correct response would be to stop the vehicle in a safe location as soon as possible. This will prevent further damage to the tire and reduce the risk of an accident. Additionally, the driver should contact a professional for assistance or replace the tire if necessary, following proper safety protocols.