Assuming that this is a compounding interest rate, we use the future value formula which is expressed as: F = P ( 1 + i )^n where F is the future value, P is the present value, i is the interest rate and n is the compounding periods. We do as follows:
F = P ( 1 + i )^n
8000 = 4000 ( 1 + 0.0553)^n
n = 12.88 yrs or about 13 years
Therefore, option D is the answer.
