What action places the elevator in Phase II mode?

The action that places the elevator in Phase II mode is achieved by pushing and holding the 'Door Close' button followed by the desired floor button. This procedure is integral to the operation of the elevator system during emergency situations, as it allows firefighters and first responders to take control of the elevator. Phase II operation is designed to ensure that emergency personnel can manually operate the elevator, allowing for safe and efficient movement to the designated floor where assistance might be needed.

In this context, pressing the 'Door Close' button signals the elevator to start its operation, while immediately following up with the desired floor button directs the elevator to the specific location intended for service. This method contrasts with phase I operation, where the elevator is normally controlled by building occupants and uses regular buttons without a specific emergency procedure.

Other actions, such as simply pressing the 'Phase II' button, do not directly initiate the necessary steps to transfer control to the emergency responders, while pulling the elevator control lever and pushing and holding the 'Door Open' button would likely interfere with operations and not achieve the intended control. The effective combination of the 'Door Close' button and the desired floor button is crucial in ensuring that the elevator operates as required in emergency conditions.