I _________ him before. But my friends _________ him two days ago. [ ]

A. didn't meet; met

B. haven't met; met

C. don't meet; meet

D. hadn't met; meet

某商场的部门和商品两个实体之间的关系如下图所示。假设每个部门负责销售若干种商品，每种商品只能由一个部门负责销售，那么部门和商品之间存在着 (14) 的联系。