Final answer:
The airspeed limitation that applies to the color-coded marking system of the airspeed indicator is A. VNE (Never exceed speed), represented typically by a red line on the airspeed indicator to alert pilots not to surpass this critical speed.
Step-by-step explanation:
The airspeed limitation that applies to the color-coded marking system of the airspeed indicator is A. VNE (Never exceed speed). The color-coding on the airspeed indicator is designed to give pilots a quick visual reference of critical airspeeds, out of which the VNE is the most crucial as it represents the maximum speed at which an aircraft can be safely flown. Exceeding VNE can result in structural failure, which is why it is marked, typically with a red line, on the airspeed indicator to alert the pilot not to exceed this limit. Other color-codings may indicate speeds such as VNO (green to yellow range), which is the Maximum structural cruising speed, and VS1 (the lower end of the green range), which stands for the Stalling speed in a specified configuration. The VNE is always marked and is a critical limit for pilot awareness.