The solid line in the saw$-$tooth graph shown below depicts the inventory level for an item controlled by a fixed$-$order$-$quantity inventory system. Which letter $($A$-$E$)$ describes the reorder $($R$)$ level $($point$)?$ You may need to use the scroll bar on the bottom of the page to see the entire diagram.

Question $16$Select one:

a$.$

letter C

b$.$

letter A

c$.$

letter B

d$.$

letter D

e$.$

letter E