What would you have measured and with what type of measurement scale?

Discussion Question Answered.–SERIOUS INQUIRES ONLY–NO GAMES–GRADUATE LEVEL WORK- 500 WORDS, APA FORMAT, 2 REFERENCES, WITH (1) BIBLICAL INTEGRATION INCLUDED.
As part of its bankruptcy restricting, General Motors (GM) launched an ad campaign that revealed glimmers of a streamlined GM: fewer brands (Cadillac, Buick, Chevrolet, and GMC) and fewer models within each brand.
What research would you have done to determine which vehicle models GM should retain and which it should drop?
What would you have measured and with what type of measurement scale?
Text Reference: 
Cooper, D. R., & Schindler, P. S. (2014). Business Research Methods. New York: McGraw-Hill Companies (included but not counted with total needed references)