It is given to us that the interest rate is 2%.
We know that 2% can be rewritten as
. Now, we also know that in decimal form,
.
Therefore, the interest earned on d dollars at an interest rate of 2% will be "2% of d" which can be rewritten as
. This is because in math, "of" means the same as multiplication.
Thus, out of the given options, the last option is the correct option.