Question

where in the plant does the light - dependent reaction happen?
leaves
thylakoid
mitochondria

Explanation:

Light - dependent reactions of photosynthesis occur in the thylakoid membranes of chloroplasts in plant cells. Chloroplasts are mainly found in leaves, but the specific site of the light - dependent reaction is the thylakoid. Mitochondria are involved in cellular respiration, not photosynthesis.

Answer:

thylakoid