Answer: Perfectly competitive market structure
Step-by-step explanation: A perfectly competitive market structure has the following characteristics:
a. Large number of firms
b. Free entry and exist of firms
c. Identical goods
d. Perfect knowledge
e. Firms are price takers and not price makers
Since, there are many plantation owners supplying to a huge number of companies with identical products and no power to fix their own prices, the market in reference has characteristics of a perfectly competitive market structure.