The circuit board for the computers your company builds have a lead time from the supplier of $4$ weeks. The economic order quantity is $250$ circuit boards. Your company pulls circuit boards from inventory at a rate of $120$ boards per week, but demand is variable so your boss wants you to keep a safety stock of $50$ circuit boards. What is the inventory policy for circuit boards? $($Slide $29)$

Group of answer choices

Order $250$ circuit boards. when circuit board inventory drops to $480$ boards.

Order $120$ circuit boards. when circuit board inventory drops to $250$ boards.

Order $530$ circuit boards. when circuit board inventory drops to $250$ boards.

Order $250$ circuit boards. when circuit board inventory drops to $120$ boards.

Order $480$ circuit boards. when circuit board inventory drops to $250$ boards.

Order $250$ circuit boards. when circuit board inventory drops to $530$ boards.