Suppose Average Total Cost Falls and Average Variable Cost Goes

Suppose average total cost falls and average variable cost goes up as one more unit of output is produced. Based on this information you would expect marginal cost to be:

A) less than both average total cost and average variable cost.
B) greater than both average total cost and average variable cost.
C) less than average total cost and greater than average variable cost.
D) greater than average total cost and less than average variable cost.