Mối quan hệ giữa lực lượng sản xuất và quan hệ sản xuất biểu hiện ra mặt xã hội là quan hệ giữa những giai cấp nào trong xã hội

Upper class and middle class.

Explanation:

The relationship between the productive forces and the social relations of production is the relationship between higher owner class and the middle class which are the workers. The term relations of production refers to the relationship between those who own the production facility or who run the facility means the capitalists and those who do not owns the facility or those who work in that production facility i.e. the workers.