Correct Response: B. Car suspensions come in a wide variety of forms but every suspension includes some sort of a spring system to hold the car up off of the road. The spring usually consists of a piece of steel that is deflected in some way as the car is weighed down. Common types of automotive springs are coil springs in the form of coils that are compressed, leaf springs in the form long flat bars that are bent, and torsion bars in the form of long rods that are twisted. Torsion bars are typically only found in the suspension system. They are usually not included in propulsion (A), guidance (C), or control systems (D).
