The polynomial f(x)=x2−4 is considered on the interval [−3,3]. Which one of the following expressions must be evaluated to obtain the unsigned area enclosed between its graph and the x-axis on this interval?
a) ∫−3−2(x2−4)dx+∫−22(x2−4)dx+∫23(x2−4)dx
b) ∫−3−2(x2−4)dx+∫−22(4−x2)dx+∫23(x2−4)dx
c) ∫−3−2(4−x2)dx+∫−22(x2−4)dx+∫23(4−x2)dx
d) 2∫02(4−x2)dx