Final answer:
The marginal product of labor curve has a a. negative slope due to diminishing returns to labor, which occurs when the additional output from each new worker decreases as more workers are added to a production process with fixed capital.
Step-by-step explanation:
The value of the marginal product of labor curve generally has a a. negative slope because of diminishing returns to labor in production. This is a reflection of the law of diminishing marginal product, which states that while adding more workers to a production process with fixed capital may increase output initially, it will eventually lead to a decrease in the additional output produced by each new worker.
This phenomenon occurs because the fixed capital (like machinery and workspace) becomes insufficient to allow all workers to be equally productive, causing the marginal gains from additional labor to diminish and eventually turn negative.