Final answer:
The connection of a garbage disposal receptacle to one of the two required small appliance branch circuits in a kitchen is optional according to the NEC, highlighting the importance of safe electrical practices.
Step-by-step explanation:
The receptacle under the kitchen counter used to supply power to a garbage disposal is considered optional to be connected to one of the two required small appliance branch circuits. The National Electrical Code (NEC) provides guidelines for the proper wiring and protection of electrical systems. According to these guidelines, it is essential to ensure that electrical appliances, especially in areas such as the kitchen, are safely connected to avoid electrical hazards such as severe shocks. This is of particular concern in environments where a ground connection is present, such as through water on the floor or a water faucet. In the event of an issue with the outlet, other appliances like a coffeemaker would also not function properly if connected to the same faulty outlet. Moreover, with a proper ground connection, any faults in the circuit would likely cause the circuit breaker to trip, prompting repairs and ensuring user safety.