Which pigment is responsible for changing the color of leaf to yellow and red?

There are 3 pigments that cause the color change in the fall. If the leaf has predominantly anthocyanins, the color will be red; if the leaf has anthocyanins and carotenoids, the predominant color will be orange; and if the leaf has mainly carotenoids, the leaf will be yellow. Chlorophyll (green) masks all of these colors until late in the season when its green pigment degrades.

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