Question

where does the light - independent reaction (calvin cycle) take place?
thylakoids
stroma
inner membrane of mitochondria
cytoplasm

Explanation:

The light - independent reaction (Calvin cycle) occurs in the stroma of the chloroplast. Thylakoids are involved in the light - dependent reactions. The inner membrane of mitochondria is related to cellular respiration (e.g., electron transport chain in oxidative phosphorylation). The cytoplasm is a general part of the cell where many metabolic processes occur but not the specific site for the Calvin cycle.

Answer:

stroma