On January 31st, 1985, Pontiac was running a series of ads urging consumers to "Buy a Grand Am for Under 10 Grand!" More specifically, they were selling such cars with an asking price of $9,995. Suppose that, taking into account current rebates, you could buy an equivalent new Grand Am on January 31st, 2003 for $20,989. What has been the yearly rate of growth in this car's price during this period?

a. 3.78%

b. 4.21%

c. 8.13%

d. 11.67%