What is one of the primary characteristics od perfectly competitive markets

The correct answer is: "many producers and all are price takers"

Perfect competitive markets are characterized by a large number of producers and each offer the same homogeneous product, this is why they have little bargaining power and they are all price-takers. Tthey cannot influence the market price at which the product is commercialized. They can only decide the amount that they will offer according to their price maximization strategies.

Markets of agricultural products are considered the best example of perfectly competitive markets in the real world.