Final answer:
Floor plans are diagrams that display the layout of a building, including emergency exits and elevators, to guide occupants to safety in an emergency.
Step-by-step explanation:
The diagrams that are required to be mounted in hallways, which show elevators, fire exits, and other important features of a building, are known as b) Floor plans. A floor plan is a scaled diagram of a room or building viewed from above. Floor plans typically include details such as walls, doors, windows, and other architectural components, as well as the locations of emergency exits, elevators, and other critical features for navigation and safety. They are used to plan evacuation routes and are crucial in emergencies for guiding occupants to safety.