Answer: a. always declines with increased levels of output.
Explanation: the average fixed cost curve graphically illustrates or shows the relation between average fixed cost a firm incurs in the short-run production of a good or service, and the quantity produced. The average fixed cost curve always declines with increases in the level of output resulting in a negatively sloped curve. This is to say that the average fixed cost is relatively high at smaller quantities of output, which then declines as the level of production increases--the more output increases, the more average fixed cost declines. Why this occurs is that a given fixed cost is spread over an increasingly larger quantity of output and as such, firms can profitably charge a lower price with increased output.