In which organ does the majority of photosynthesis take place?

A. Vascular tissue

B. Stems

C. Leaves

D. Roots

The correct answer is C. Leaves. That's because they are full of chloroplasts that have a lot of chlorophyll in them. That's why they are green. The greener they are the more they have and the more sun they absorb, which is why coniferous plants have dark green colors. They need to be able to absorb what little sun there is.