GKFix MCQ Question

What is the equilibrium constant for the reverse reaction of aA + bB ⇌ cC + dD?

• A. K'c = [C]^c[D]^d / ([A]^a[B]^b)
• B. K'c = [A]^a[B]^b / ([C]^c[D]^d)
• C. K'c = [C][D] / ([A][B])
• D. K'c = [A][B] / ([C][D])