Which are the coordinates of the vertices of the reflected figure when triangle DEF is reflected across the x-axis?

a
D'(0, 3)

E'(3, 1)

F'(–3, 2)

b
D'(0, 3)

E'(3, –1)

F'(–3, –2)

c
D'(0, –3)

E'(–3, 1)

F'(3, 2)

d
D'(3, 0)

E'(–1, –3)

F'(–2, 3)