Which of the following event templates should be used when sourcing a commodity product that is a subject to frequent price fluctuations, and where participants bid in discounts relative to a baseline?

Which of the following event templates should be used when sourcing a commodity product that is a subject to frequent price fluctuations, and where participants bid in discounts relative to a baseline?
A . Index-based auction
B. Traffic light auction
C. Total cost auction
D. Reverse auction with a bid transformation

Answer: A