How can backfeed occur?

Backfeed occurs when electricity flows in the reverse direction from the intended flow, which can happen due to several factors. The correct answer highlights that one way backfeed can occur is through electricity feeding back through the load and generating induction in transformers or motors.

When a transformer or motor is energized, it can create a magnetic field. If the power source is interrupted and there is still energy stored in the system, this magnetic field can induce a current that flows back toward the source or in an unintended direction. This phenomenon is especially important in systems with distributed generation, such as solar panels, where energy can flow back into the grid during a power outage.

In contrast to the other options, this answer reflects the complexities of how electricity interacts with various components in the system. A direct connection to the source is not necessary for backfeed; faults in the system may lead to problems, but they are not the sole means of backfeed; and a well-designed system, while it may mitigate the risk of backfeed, does not completely eliminate the possibility of such occurrences under specific conditions.