An energy drink like Red Bull is usually not considered a competitor of coffee brands such as Nespresso or Starbucks. However, since both coffee and energy drink fulfill a similar need (i.e., staying awake/getting energy), customers might switch from one to another if they feel that prices increase too much in either coffee or energy drinks. This will ultimately affect an industry's profitability. Michael Porter, in his books on competitive strategy, discusses generic strategies driven by keeping costs down and prices competitive. Using a positioning matrix, what should Red Bull map? a. Low price vs. high quality b. High price vs. high quality c. Heavy users vs. high quality d. Substitute products vs. high price