Final answer:
When a relay is energized, the Normally Open contact is closed, completing the circuit, while the Normally Closed contact opens.
Step-by-step explanation:
When a relay with both Normally Open (NO) and Normally Closed (NC) contacts is energized, the Normally Open contact is closed. In a typical relay configuration, the NO contact forms a circuit when the relay coil is powered, thus closing the circuit. Conversely, the NC contact operates in the opposite manner; it is closed when the relay is not energized and opens when the relay is energized.