Answer: D. Six Sigma Methodologies
Explanation:
Six sigma methodologies are a set of tools and techniques used to effect continuous improvements of a process,this improvements is aimed at reducing wastages or variations.
Six sigma uses tools such as DMAIC(DEFINE, MEASURE,ANALYSE ,IMPLEMENT,CONTROL) etc guide the process improvement process.
There are several other tools and techniques used they include FISHBONE DIAGRAM, MEASUREMENT SYSTEM ANALYSIS(MSA), 5S etc all these are implemented in different stages of the process.