The feature of tri-color VASI is _______ .

The feature of tri-color VASI is _______ .

A.one light projector with three colors, with the amber light indicating the proper glide path

B.two visual glide paths for the runway

C.one light projector with three colors: red, green and amber

D.three glide paths, with the center path indicated by a white light

正确答案是C