What must not be used for radar or non-radar separation in data blocks?

The option stating that "Information in data blocks" must not be used for radar or non-radar separation is correct because data blocks contain critical information designed to assist controllers in maintaining aircraft separation and situational awareness. However, they are not always the primary source for separation criteria. Separation should be based on the standard separation parameters, which are defined by radar capabilities, flight rules, and airspace considerations. Therefore, while data blocks can provide valuable information such as identification, altitude, and heading, they are meant primarily to support the controller's situational awareness rather than serve as the definitive basis for separation demands.

The other options refer to aspects that are foundational to separation standards. Standard separations are the guidelines used to ensure adequate distance between aircraft. Indicated speeds provide necessary information for maintaining safe distance based on the performance characteristics of the aircraft. Altitudes for coordination are essential for ensuring that traffic levels remain safe, as altitude is a primary factor in vertical separation management. These elements are integral to the decision-making process for both radar and non-radar separation, reinforcing the idea that they are fundamentally different from the information provided in data blocks.