Which of the following describes the parabola with the equation y = −x2 − 3x + 6?
A) The axis of symmetry is x = 1.5 and the vertex is (1.5, 12.75).
B) The axis of symmetry is x = −1 and the vertex is (−1, −3).
C) The axis of symmetry is x = −1.5 and the vertex is (−1.5, 8.25).
D) The axis of symmetry is x = 0 and the vertex is (0, 6).