What should you do if a rear tire goes flat?

Answer: B — The vehicle will sway back and forth

When a rear tire goes flat, the weight distribution and balance of the vehicle will often cause it to sway back and forth. This swaying occurs because the flat tire alters the vehicle's handling dynamics, creating instability. Drivers may feel a sudden pull to one side or experience difficulty in controlling the vehicle, which can lead to swaying motions. The other choices do not accurately characterize what happens during a rear tire blowout. The vehicle does not immediately stop functioning; it can still roll, albeit with diminished control. It also doesn’t lose all acceleration; rather, the driver may lose traction or have a harder time accelerating smoothly. Additionally, while one might experience a pull to one side due to a flat tire, the primary sensation and consequence of a flat rear tire is the swaying, reflecting an unstable driving condition that must be addressed for safety.