The state should gradually establish () the agricultural product market system and formulate the development plan of agricultural product wholesale market. Unity B. Openness

Article 27 of the Agriculture Law stipulates: "The State shall gradually establish a unified, open and competitive agricultural product market system and formulate the development plan of agricultural product wholesale market. The state supports rural collective economic organizations and farmers' professional cooperative economic organizations to establish wholesale markets and bazaars for agricultural products. "Therefore, the correct answer to this question is ABCD.