Which of the following is equal to the rational expression when x ≠ 4 or 3?
a. (x - 2)(x + 2) / x
b. (x - 2)(x + 2) / (x - 3)
c. (x - 2)(x + 2) / (x + 3)
d. (x - 2)(x + 2) / (x - 4)