The Rate Law of a Reaction Is Rate = K[D][X]

The rate law of a reaction is rate = k[D][X]. The units of the rate constant are _ _.

A) L mol^{- 1}s^{- 1}
B) L² mol^{- 2}s^{- 1}
C) mol² L^{- 2}s^{- 1}
D) mol L^{- 1}s^{- 1}
E) mol L^{- 1}s_{- 2}