Lean Management emphasizes the idea of "pull" in production processes. Which of the following best describes the idea behind "pull"?

a		Pull is based on the philosophy that we will produce when orders come in, but need to keep extra inventory on hand in case there is variation.
b		Pull is based on the philosophy that we will produce in exactly the quantity that is predicted by demand forecasts.
c		Pull is based on the philosophy that an activity does not need to be performed unless there is ACTUAL demand for that activity.
d		Pull is based on the philosophy that if you run out of inventory you can usually expedite shipping to meet production schedules.