Which signal color combination on the ramp indicates 'exercise extreme caution'?

• A. Alternating red and green
• B. Flashing green
• C. Steady red
• D. Flashing white

Answer: (A)

On the ramp, signals use color and flashing patterns to tell you exactly what to do in different safety situations. Alternating red and green is used to convey exercise extreme caution, signaling that hazards are present and you should slow down, stay alert, and be ready to stop if anything unsafe appears. It stands out from other signals by indicating a higher level of caution than a simple proceed-or-stop instruction.

Steady red means you must stop and not proceed. Flashing green is typically a normal clearance to move, not a heightened warning. Flashing white is used for other operational instructions and doesn’t convey extreme caution. So the pattern that best communicates the need for heightened alertness is the alternating red and green.