Which component needs to be bonded to the grounding system?

The correct answer identifies that any metallic raceway enclosing conductors needs to be bonded to the grounding system. This bonding is crucial for safety, as it ensures that any fault currents that may occur due to insulation failure or equipment malfunction have a safe path to ground. If a fault occurs, the metallic raceway can become energized, potentially posing a significant shock hazard. By bonding the raceway to the grounding system, it not only helps to stabilize the electrical system but also reduces the risk of electric shock and fire hazards.

Metallic raceways provide protection for conductors and can also serve as a grounding means, but for this purpose to be effective, they must be properly bonded. The grounding system plays a key role in the overall electrical safety of a building, making the proper bonding of metallic components essential for ensuring the effectiveness of the grounding system and protecting both equipment and individuals from possible electrical hazards.

In contrast, insulated wire and plastic conduits do not conduct electricity and therefore do not require bonding to the grounding system. Wooden structures are non-conductive and thus do not pose the same risks as metallic components, making them irrelevant in this context.