Which of the following statements is true? a. At equilibrium BOTH the rate of the forward reaction equals that of the reverse reaction AND the rate constant for the forward reaction equals that of the reverse. b. The equilibrium state is dynamic even though there is no change in concentrations. c. The equilibrium constant for a particular reaction is constant under all conditions. d. Starting with different initial concentrations will yield different individual equilibrium concentrations and a different relationship of equilibrium concentrations. e. None of these is true.