Answer:
The correct answer is the first option: Always has a positive slope.
Step-by-step explanation:
To begin with, the marginal cost curve of a firm is the graphical representation the relationship between the last unit produce and the cost of producing it. Therefore that this concept shows how much it cost to the company to produce one more unit of the product. Moreover, due to the fact that the relationship between the production and its costs are directly, the slope of the curve will be always positive, meaning that if the production increases then obviously the costs will increase but the cost per unit might decrease due to the volumen handle by the organization.