The width, w, of a rectangle garden is x - 2. The area of the garden is x^3 - 2x - 4. What is an expression for the length of the garden?
a. x^2 -2x - 2
b. x^2 + 2x - 2
c. x^2 - 2x + 2
d. x^2 + 2x + 2