An air defense warning uses color codes to indicate degree of air raid probability. Which color means attack by hostile aircraft or missiles is imminent or in progress?

• A. Red
• B. Green
• C. White
• D. Yellow

Answer: (A)

The key idea is how color cues convey threat urgency at a glance. Red signals the highest level of warning: an attack by hostile aircraft or missiles is imminent or already in progress, so immediate protective actions must be taken. This color communicates maximum urgency so personnel and systems can react without delay.

In this system, other colors indicate lower urgency: yellow means an increased alert or potential threat but not yet imminent, green usually denotes normal or safe conditions, and white often represents all-clear or non-threat status depending on the specific protocol. Red stands out as the trigger for rapid, decisive action.