Answer:
d. All of the above
Step-by-step explanation:
The six sigma is a method where it provides the tools to the organization in order to improve the business process ability. This result in rise in performance and reduce the variation in the process due to which it decreased the defects and have improvement in the profits, morale of the employees and the product's quality
So as per the given situation it purpose is to discover and eliminate the mistakes, decrease the variability and also decreased the cost
Therefore the option d is correct