Final answer:
A unit of an electrical system that is designed to carry but not utilize electrical energy is a Conductor. Conductors allow electric charge to move through them easily, unlike capacitors which store charge, and resistors which dissipate power.
Step-by-step explanation:
The question asks us to identify a unit of an electrical system that is designed to carry but not utilize electrical energy. The correct answer is d) Conductor. A conductor is a material through which electric charge can easily move. Other components like a capacitor, inductor and resistor have different functions. A capacitor is used to store electric charge and energy.
It does this by separating equal amounts of positive and negative charge on two plates, which remain close to each other but are not touching. Electromotive force (emf) is relevant for battery function but it is not the correct answer to this question. A resistor is designed to dissipate power by impeding the flow of electric current thus it also does not fit the description.