The Disproportionation of NO to N₂O and NO₂ Is Third $\rightarrow$

The disproportionation of NO to N₂O and NO₂ is third order in NO.
3 NO(g) F $\rightarrow$ N₂O(g) + NO₂(g)   rate = k (NO) ³
What are the units for the rate constant, k?

A) M³/s
B) M²/s²
C) M ^{- 3} s ^{- 1}
D) M ^{- 2} s ^{- 2}
E) none of these