Michelle deposited a certain sum of money in a savings account on July 1st, 2007. She earns an 12% interest compounded semiannually. The sum of money in the account on December 31st, 2009 is approximately what percent of the initial deposit? Choose the correct choice from the following answers:
A) 117 % B) 120 % C) 121 % D) 133 % E) 140 %

Rationale: "since michelle earns 12 % interest compounded semiannually , then she earns 6 % interest every 6 months . now , the simple interest earned in 5 periods ( 30 months = 5 * 6 months ) would be 6 % * 5 = 30 % . but , since the interest iscompoundedevery 6 months , then there would be interest earned on interest ( very small amount ) thus the actual interest earned would be a little bit more than 30 % , only answer choice d fits . answer : d"
Answer: D