The correct answer is C. straight line.
Average fixed cost (AFC) is the total fixed cost divided by the number of units produced. It is a measure of the cost per unit of output that is due to fixed costs. Fixed costs are costs that do not change with the level of output, such as rent, insurance, and depreciation.
The average fixed cost curve is a downward-sloping straight line. This is because the total fixed cost is constant, so as the number of units produced increases, the average fixed cost decreases.
A parabola is a U-shaped curve. A circle is a round shape. A rectangular hyperbola is a curve that has two branches that are mirror images of each other.
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