-14 + 21 = 7 and -24 + 17 = -7. Therefore, -14 + 21 ≠ -24 + 17
16 + (-6) = 16 - 6 = 10 and 24 + (-13) = 24 - 13 = 11. Therefore, 16 - (-6) is not greater than 24 + (-13).
-14 + (-10) = -14 - 10 = -24 and 2 + (-28) = 2 - 28 = -26. Therefore, -14 + (-10) > 2 + (-28)
Therefore, statement C is true.