DENDROLOGY

Detailed explanation-1: -Although both chlorophyll a and chlorophyll b absorb light, chlorophyll a plays a unique and crucial role in converting light energy to chemical energy (as you can explore in the light-dependent reactions article).

Detailed explanation-2: -Note: Chlorophyll b is the accessory pigment which will transfer the light to the chlorophyll a. It is bonded to the porphyrin functional group. Phycobilins are the light-harvesting pigments. They absorb the red, green and yellow colour wavelengths, which are not absorbed well by the chlorophyll a.