How do you denote released discretion on a strip?

To denote released discretion on a strip, the correct choice involves using the phrase "SYD/call sign." This notation is part of standard procedures that help pilots and controllers identify the terms under which a flight is operating. In this context, "SYD" typically refers to "Subject to Your Discretion," indicating that the pilot has the authority to maneuver the aircraft as necessary within the parameters established by air traffic control.

This terminology is essential because it communicates to both the pilot and the controller that certain aspects of the flight, such as altitude adjustments or navigation decisions, are under the pilot's discretion, thereby facilitating more flexible and efficient flight operations. The call sign following "SYD" designates the specific aircraft being referenced, ensuring clear communication and reducing the chances of confusion.

The other choices do not accurately represent the standard method for denoting released discretion. The use of "ATC/clearance," "SFC/altitude," or "DISCRETION/flight level" would not convey the same message or align with established protocol for indicating operational flexibility for pilots. Each term fails to encapsulate the necessary context needed for understanding the authority transferred to the flight crew.