What must be done with remarks that are pertinent to the control of the flight?

The correct choice involves coordinating pertinent control remarks with the R-side. This process is crucial because effective communication and coordination between controllers play a vital role in ensuring the safety and efficiency of flight operations. By sharing relevant information related to control, all parties involved can maintain situational awareness and respond appropriately to changing conditions, ultimately enhancing the overall management of flight operations.

In air traffic control, the R-side typically refers to the radar side of the operation, where radar data and tracking information are utilized for an accurate assessment of flight paths. Sharing remarks that directly affect flight control ensures that all controllers involved have the necessary information to make informed decisions, particularly in complex or rapidly changing circumstances.

Other options involve actions that may not contribute directly to the collaborative decision-making process or may not be appropriate in all situations. Keeping information confidential could hinder safe operations if critical data is not communicated. Documenting remarks for future reference can be important, but it does not facilitate immediate operational communication. Discussing control remarks with other controllers is beneficial but may not specifically require coordination with the R-side, which is essential for real-time flight management.