A production manager at a pottery factory has noticed that about 70 percent of defects result from impurities in raw materials, 15 percent result from human error 10 percent from machine malfunctions, and 5 percent from a variety of other causes. This manager is most likely using: a.A quality loss function. b.A scatter diagram. c.A Pareto chart. d.A flowchart. A cause-and-effect diagram.