Question: Upon receiving a Floor Taken message from the floor control server interface, what actions does the floor participant interface toward the MCPTT client take if the first bit in the subtype of the Floor Taken message requires acknowledgement?
Option 1: It sends a Floor Ack message immediately and transitions to 'P: has permission' state.
Option 2: It only sends the Floor Taken message to the MCPTT floor participant without any further action.
Option 3: It sends the Floor Taken message to the MCPTT floor participant, stores an indication that a Floor Ack message is expected, and remains in the 'P: has no permission' state.
Option 4: It ignores the acknowledgement bit and releases any previously held floor.
Explanation: This option correctly reflects the specified behavior when the first bit in the subtype of the Floor Taken message indicates that acknowledgement is required. The interface not only forwards the message but also tracks the need for a subsequent Floor Ack message, all while maintaining its current permission state ('P: has no permission'). This ensures proper communication flow and state management within the MCPTT system.