Which of the Following Is the Correct Way to Describe

Which of the following is the correct way to describe equilibrium in a market?

A) At equilibrium, demand equals supply.
B) At equilibrium, quantity demanded equals quantity supplied.
C) At equilibrium, market forces no longer apply.
D) Equilibrium is a tendency for price to change, a state of perpetual motion.
E) At equilibrium, the "fairest" price for output is achieved.