The production supervisor noticed an unfavorable Direct Materials Quantity Variance and decided to investigate. When speaking to the line employees, it was discovered that there was a lot of rework being done in production because the quality of the materials was inferior to what they normally worked with. Based on this information and responsibility accounting, who is responsible for the unfavorable Direct Materials Quantity Variance? A. The purchasing supervisor for buying inferior quality materials. B. The factory line workers for not adjusting to the lower quality materials. OC. The production supervisor because all production variances are his responsibility. D. The CEO because ultimately all responsibility belongs to the CEO