Why is an electrical service grounded?

Grounding an electrical service is primarily done to stabilize the voltage during normal operation. When a system is grounded, it provides a reference point for the electrical system's voltage levels, which helps ensure that the voltage remains at a safe, consistent level during operation.

Grounding creates a pathway for excess electrical charge to safely dissipate into the earth, preventing any unintended accumulation of charge that could lead to overvoltage conditions. This is particularly important to protect both the equipment and the people using it from voltage surges or faults.

In addition to stabilizing voltage, grounding also serves other important safety functions, such as protecting against lightning strikes and short circuits, but the main purpose tied to the given option is to maintain voltage stability throughout the system's operation.