Which tool is essential for making permanent electronic connections?

The soldering iron is essential for making permanent electronic connections because it allows for the melting of solder, a metal alloy, to join electronic components, wires, or circuit board pads together. When solder is heated with the soldering iron, it becomes liquid and flows into the joint, and upon cooling, it solidifies to form a strong, conductive connection. This process is fundamental in electronics, where reliable and durable connections are crucial for the device's functionality.

In contrast, while wire strippers are important for preparing wires by removing their insulation, they do not make connections themselves. A multimeter is used for measuring electrical properties such as voltage, current, and resistance, but it does not create connections. Similarly, a cable tester checks the integrity and functionality of cables but does not join components together. Thus, the soldering iron stands out as the tool that specifically facilitates the permanent joining of electronic components.