Which pneumatic component provides straight line motion?

The cylinder is the component that provides straight line motion in a pneumatic system. It converts the energy supplied by compressed air into linear motion. When compressed air enters the cylinder, it acts on a piston inside, pushing it back and forth along a defined path. This motion is typically used to move, lift, or press objects in various applications, making cylinders crucial for tasks that require precise linear movement.

In contrast, a motor usually converts electrical energy into rotary motion rather than linear motion. A Directional Control Valve (DCV) is responsible for directing the flow of air within the system and does not provide motion itself. Lastly, a muffler serves to reduce noise from the escaping air but has no function in providing motion. Thus, the role of the cylinder in facilitating straight line movement makes it the correct answer.