The minimum size of the single bonding jumper in Section 1 is ___ AWG.

The minimum size of the single bonding jumper specified in the National Electrical Code (NEC) is 1/0 AWG. This requirement is established to ensure proper grounding and bonding in electrical installations, which are critical for safety and reliability. The bonding jumper serves to connect the grounding system to various metallic structures, thus providing a low-resistance path for fault currents and minimizing the risk of electrical shock or fire.

A bonding jumper that is sized at 1/0 AWG is generally capable of carrying sufficient fault current while ensuring that the voltage on exposed conductive parts is minimized. The use of larger gauge wire helps ensure that the bonding system can handle the maximum expected ground fault currents without overheating or becoming ineffective.

Understanding the sizing requirements for bonding jumpers is key for installing safe and compliant electrical systems. Being aware of the proper sizes helps electricians make informed decisions during installation and maintenance to uphold electrical safety standards. The other options fall below the minimum requirement or do not align with the NEC specifications for bonding jumpers in typical applications.