Which inequality represents the statement "-9x² is greater than 18 or 13x + 15 is less than or equal to -4"?

a) -9x² > 18 or 13x + 15 ≤ -4
b) -9x² < 18 or 13x + 15 ≥ -4
c) -9x² ≥ 18 or 13x + 15 < -4
d) -9x² ≤ 18 or 13x + 15 > -4