For the gas phase reaction A + B -> C + D, where Kp = 100 at a given temperature, if we start with 1 mol/L of each of the four substances, which of the following statements is/are true?
a. The reaction will proceed to the right until equilibrium is reached.
b. The concentration of A and B will decrease as the reaction proceeds.
c. The concentration of C and D will increase as the reaction proceeds.
d. The equilibrium concentration of A, B, C, and D can be calculated using the equilibrium constant Kp.