What is the primary function of the light reactions of photosynthesis?
a) to produce energy-rich glucose from carbon dioxide and water
b) to produce atp and nadph
c) to produce nadph used in respiration
d) to convert light energy to the chemical energy of pgal
e) to use atp to make glucose

The correct answer will be option-B.

Explanation:

Photosynthesis occurs in two stages: light-dependent and light-independent reaction.  The light-dependent reaction is the reaction which takes place in the sunlight and converts light energy to chemical energy.

The reaction stores chemical energy in the form of energy equivalents mainly ATP through chemiosmosis and NADPH. These molecules are used in the second phase of the photosynthesis that is light-independent reactions where glucose is synthesized.

Thus, Option-B is the correct answer.