A Reaction with an Equilibrium Constant K_c = 1

A reaction with an equilibrium constant K_c = 1.5 x 10²¹ would consist of which of the following at equilibrium:

A) approximately equal reactants and products
B) some reactants and products with reactants slightly favored
C) some reactants and products with products slightly favored
D) essentially all reactants
E) essentially all products