Find the x-values of all points where the function has any relative extrema. Find the value(s) of any relative extrema. f(x) = x³ + 3x² + 9x+1 Select the correct choice below and, if necessary, fill in any answer boxes within your choice. A. There are no relative maxima. The function has a relative minimum of (Use a comma to separate answers as needed.) at x= OB. There are no relative minima. The function has a relative maximum of (Use a comma to separate answers as needed.) at x= C. The function has a relative minimum of 0 at x = -1 and a relative maximum of 0 at x= (Use a comma to separate answers as needed.) O D. There are no relative extrema.