What will happen if ATP and NADPH are already used up at night?

If ATP and NADPH are already used up at night , the production of glucose will stop.

Explanation:

IMPORTANCE OF ATP AND NADPH -: To temporarily store energy, the light-dependent reactions generate ATP and either NADPH or NADH. In light-independent reactions, these energy carriers are used to drive the energetically unfavorable mechanism of "fixing" organically inorganic CO2.

ATP is the molecular energy "currency" in biological systems. All energy produced by living organisms' cellular respiration must end up being used as ATP to power it. NADPH is a hydrogen carrier molecule reduced by NADP (Nicotinamide Adenine Dinucleotide Phosphate). While the light-dependent reactions take place, energized electrons hop on to electron carriers excited by photon energy from the sun (On Photosystem 2) and finally get to Photosystem one.

correct answer is a. and d.