Final answer:
All conductors of the same circuit, including grounded (neutral) and equipment grounding conductors, must be contained in the same raceway, cable, or trench according to the NEC. This is to ensure proper grounding and safety of electrical systems, with the answer being (d) all of these.
Step-by-step explanation:
Electrical grounding is essential for the safety and proper operation of electrical systems. Grounding ensures that in the event of a fault, electricity has a direct path to the earth, which can help prevent dangerous situations such as electrical shock or fires.
According to the National Electrical Code (NEC), all conductors of the same circuit, including the grounded (neutral) and equipment grounding conductors, and bonding conductors must be contained within the same raceway, cable, or trench, which is a safety measure to ensure that all components of the electrical system are properly grounded and to minimize the risk of electric shock or fire. Therefore, the answer to the question is (d) all of these.