Which of the following is equal to the rational expression when x ≠ 5 or -1? [tex] \frac{(x-7)(x+1)}{(x+1)(x-5)} [/tex]a. [tex] \frac{x+1}{x-7} [/tex]b. [tex] \frac{x+1}{x-5} [/tex]c. [tex] \frac{x-7}{x+1} [/tex]d. [tex] \frac{x-7}{x-5} [/tex]

When x ≠ 5 and x ≠ -1, the expression can be simplified by cancelling the common factor in the numerator and denominator, namely (x+1) to leave us with (x-7) / (x-5), for which there is only one valid choice out of the four.