The correct answer is: C. Their respective minimas.
The marginal cost (MC) curve cuts the average variable cost (AVC) and average total cost (ATC) curves at their respective minimas. This is because the MC curve represents the additional cost of producing one more unit of output, while the AVC and ATC curves represent the average cost of producing all units of output. When the MC curve is below the AVC and ATC curves, it means that producing one more unit of output will lower the average cost of production. However, when the MC curve is above the AVC and ATC curves, it means that producing one more unit of output will increase the average cost of production. The MC curve will therefore intersect the AVC and ATC curves at their respective minimas, which are the points at which the average cost of production is lowest.
Here is a diagram that illustrates this concept:
[Diagram of MC, AVC, and ATC curves]
The MC curve intersects the AVC curve at point A, which is the minimum point of the AVC curve. The MC curve intersects the ATC curve at point B, which is the minimum point of the ATC curve.
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