The gas piping must be considered bonded when it is connected to what?

The correct choice emphasizes that gas piping must be considered bonded when it is connected to appliances that utilize the grounding conductor of the circuit. This bonding is crucial to ensure safety and compliance with electrical codes, preventing potential electrical hazards. When a gas appliance is bonded to the grounding system, it creates a path for fault current to safely travel to ground, which can help protect both people and property from electrical shock and fire hazards.

Grounding and bonding mechanisms are integral in any gas installation. If a gas appliance, like a gas stove or furnace, is connected to the electrical system via its grounding conductor, it helps mitigate any electrical faults, reducing the risk of dangerous voltage on the piping.

Other options, while they may involve interactions with gas appliances, do not adequately reflect the fundamental safety principles addressed by bonding. For instance, stating any appliance without consideration for grounding lacks the specificity required for safe practices. Similarly, limiting bonding requirements to gas meters or non-electric appliances doesn't encompass the necessary scope to ensure safety across various types of installations and scenarios where gas appliances may be present.