Prices fall or climb depending on quantity. With cocoa, since the prices are falling, it means there is excess supply. With the byproducts, there is excess demand, which makes prices sky rocket. See, people like being able to buy things cheap, so that's how cocoa is bought. The byproducts are sold at higher prices because the products can get more and more money as people begin to want more and more of the product. So, I'd say that your combination would be C and D, though I'm not entirely positive. I hope I'm helping some!