About 20 years ago, Xx-zobam, Inc., produced a sturdy, lightweight backpack in a market that was rapidly growing. Sturdy Light became a leader in this market. Eventually, the backpack market reached the maturity stage and slowed down. However, by this time, Xx-zobam had developed a strong brand name and continued to steadily lead the market. Which of the following describes this scenario?
a. sturdy light was a star that developed into a cash cow.
b. sturdy light was a question mark that developed into a star.
c. sturdy light was a dog that developed into a question mark.
d. sturdy light was a cash cow that developed into a star.