We need to simplify this number. We begin by evaluating the numbers inside the equation. We can simplify this to:
[tex](2 \sqrt{k})^{-2} [/tex]
Now, we evaluate this one step further. Because a negative exponent makes the number 1 over what it was, we can make this problem:
[tex] \frac{1}{(2 \sqrt{k})^{2} } [/tex]
This becomes:
[tex] \frac{1}{(2 \sqrt{k})(2 \sqrt{k} ) } --\ \textgreater \ \frac{1}{4k} [/tex]
So, 1/4k is the answer. This is the same as C, so C is the right answer.