Carefully analyze the three sentences provided below. Certain noun phrases have been highlighted and labeled with corresponding letters. Identify the exact pair or pairs of phrases that must be interchanged across the different sentences to make them all grammatically flawless and contextually accurate. Choose the correct option accordingly. I. Was the diplomatic delegation instructed that aviation security protocols (

• A must be enforced smoothly while managing traffic for visiting foreign dignitaries? II. Air traffic control reported that regular commercial flights (
• B were applied strictly across the international airport runway during the high-level summit. III. Ensure that centralized traffic diversions (
• C are not delayed despite heavy movement around the international airport terminal.