A recent advertisement in the financial section of a magazine carried the following claim: "Invest your money with us at 12 percent, compounded annually, and we guarantee to triple your money sooner than you imagine." Ignoring taxes, how long would it take to triple your money at a rate of 12 percent, compounded annually?

a Approximately 6.1 years

b Approximately 5.3 years

c Approximately 8.4 years

d Approximately 9.7 years