A sum of money place at compound interest doubles itself in 4 years. In how many years will it amount to eight times itself?	Select the correct option:  A) 33  B) 77  C) 12  D) 88  E) 11
100 ---- 200 ---- 4   400 ---- 4   800 ---- 4   ------   12 years   Answer: 12
<result>C</result>
A sum of money place at compound interest doubles itself in 4 years. In how many years will it amount to eight times itself?