A light $y$ should illuminate when neither room $b$ is occupied nor room $c$ is occupied. The functionality can be captured as $y=(b+c).\text{'}$ Which of the following is equivalent? The light should illuminate when room b is occupied and room c is occupied. The light should illuminate when room b is not occupied or room $c$ is not occupied. The light should illuminate when room b is occupied or room c is occupied. The light should illuminate when room $b$ is not occupied and room $c$ is not occupied.