When in the process of trying to identify the critical x's for a lean project. A PI lead creates a __________ because frequently its 20% of the inputs that have an 80% impact on the output.

When in the process of trying to identify the critical x’s for a lean project. A PI lead creates a __________ because frequently its 20% of the inputs that have an 80% impact on the output.
a. Pareto Chart
b. FMEA
c. Control Chart
d. X-Y Diagram