the risk of grade a is very small. For global suppliers in audi ag, the supplier quality risk level is divided into four levels: ABCD, A-level risk is very small, B-level risk is small, C-level risk is moderate, D-level risk is high, and public risk supplier level is A-level risk is very small. Volkswagen is an automobile manufacturing company headquartered in Wolfsburg, Germany, and the core enterprise of Volkswagen Group, one of the four largest automobile manufacturers in the world.