The chemical energy stored in atp during photosynthesis is released during the dark phase to

a. produce o2
b. produce co2
c. release energy for the "light"
d. produce a carbohydrate from co2

d) produced carbohydrate from CO₂

Explanation:

Photosynthesis:

It is the process in which in the presence of sun light and chlorophyll by using carbon dioxide and water plants produce the oxygen and glucose.

Carbon dioxide + water + energy →   glucose + oxygen

water is supplied through the roots, carbon dioxide collected through stomata and sun light is capture  by chloroplast.

Chemical equation:

6H₂O + 6CO₂ + energy  →   C₆H₁₂O₆ + 6O₂  

The energy stored in the form of ATP is used to form the carbohydrate from  CO₂. The carbon dioxide is taken from air and by adding the hydrogen converted into carbohydrates.