What tool is used to flatten tires?

The tire valve stem is the correct tool used to flatten tires because it is the component that controls the air pressure within the tire. By removing or adjusting the valve stem, air can be released from the tire, leading to deflation. When the valve stem is depressed, it opens a small valve that allows air to escape, effectively flattening the tire. This method is straightforward and allows for controlled deflation, making it a practical choice in various scenarios involving vehicle rescue or tire management.

The other tools are not suitable for flattening tires in the same way. An air compressor is used to inflate tires, not deflate them. A jack is intended for lifting the vehicle to access the tires but does not affect tire pressure. Similarly, a pneumatic wrench is designed for loosening or tightening bolts and does not have any mechanism to alter tire inflation. Understanding the function of the tire valve stem is crucial for effective vehicle rescue and maintenance operations.