Answer:
The answer is the first one
Explanation:
This is a difference of squares, meaning the first term is a perfect square, and the second term would be a perfect square if it were not negative. To factor it, find the square root of both the first an second term, the square root of 9x^4 is 3x^2 and the square root of 64 is 8. Put both of those numbers into 2 separate sets of parenthesis and one set will have + in between and the other will have -. It will look like the first option