Why Do Reversible Reactions in a Cell Rarely Reach Equilibrium

Why do reversible reactions in a cell rarely reach equilibrium?

A) because the products are generally reactants in other reactions and are thus immediately used
B) because most reactions in a cell are not reversible, thus allowing the cell to devote additional resources to regulating the few reversible reactions that do occur
C) because cells have no way of measuring the relative ratios of reactants and products
D) because a cell at equilibrium is dead