Which points are the best approximations of the relative maximum and minimum of the function?

f(x)= x³+3x²-9x-8

a. the relative maximum is at (3, -13) and the relative minimum is at (-3, -19)
b. the relative maximum is at (-3, 19) and the relative minimum is at (1, -13)
c. the relative maximum is at (3, -13) and the relative minimum is at (3, -19)
d. the relative maximum is at (-3, -19) and the relative minimum is at (-1, -13)