Which among the following pigments is essential for the sustenance of almost all life on earth?
Chlorophyll.
Chlorophyll is the pigment that traps light energy so that the plant can make food. Since plants provide food directly or indirectly to almost all heterotrophs on this planet, chlorophyll is essential for almost all life on earth. Chloroplasts are not pigments but are organelles present in the plant cell that contain the chlorophyll. Chlorophyll is called a pigment because it imparts green color to the plant.