Question

during which stage of photosynthesis is oxygen produced?
○ calvin cycle
○ electron chain
○ light independent
○ light dependent

Explanation:

Photosynthesis has two main stages: light - dependent and light - independent (Calvin cycle). In the light - dependent reactions, water molecules are split (photolysis) to provide electrons for the electron transport chain, and this process releases oxygen as a by - product. The Calvin cycle (light - independent) is about carbon fixation and doesn't produce oxygen. The "electron chain" is part of the light - dependent reactions but not the stage name for oxygen production. So the stage where oxygen is produced is the light - dependent stage.

Answer:

D. light dependent (assuming the options are labeled A - D as: A. Calvin cycle, B. electron chain, C. light independent, D. light dependent)