Addison, Inc -Under the _____ Inventory Method, Accounting Records Maintain a Continuously

Addison, Inc. uses a perpetual inventory system. The following is information about one inventory item for the month of September:
$\begin{array} { r l l } \text { Sept. } 1 & \text { Inventory } & 20 \text { units at } \$ 20 \\ 4 & \text { Sale } & 10 \text { units } \\ 10 & \text { Purchase } & 30 \text { units at } \$ 25 \\ 17 & \text { Sale } & 20 \text { units } \\ 30 & \text { Purchase } & 10 \text { units at } \$ 30 \end{array}$
-Under the _____ inventory method, accounting records maintain a continuously updated inventory value.

A) retail
B) periodic
C) physical
D) perpetual