Assume a manufacturer has six distribution centers in the United States, including distribution centers attached to its two manufacturing plants. Which of the following best explains how a manufacturer's total amount of inventory in its distribution network changes as it decreases the number of distribution centers that it has in its network? Question 4 options: a) Total inventory is uncorrelated with the number of distribution centers. b) Total inventory decreases at a constant (i.e., linear) rate as more distribution centers are eliminated. c) Total inventory decreases at a decreasing rate as more distribution centers are eliminated. d) Total inventory decreases at an increasing rate as more distribution centers are eliminated