The correct answer is - Producers demand labor, and workers supply labor.
Every producer with its production facilities needs a labor force in order to be able to produce what he/she has in mind and has set the terrain for. From the other side, the workers are the ones that provide the necessary labor force that the producers are demanding for their production facilities.
In order for both sides to be happy, and get what they want and need, while respecting each other for the benefit of both sides, they always need to find a middle ground and understanding, so that they can create a nice environment for production.