$5)$ In a drive$-$in fast food restaurant, customers form a single lane, place their order and pay their bill at one window, and then pick up their food at a second window. This queuing configuration is referred to as:

A$)$ single$-$server, multiphase system

B$)$ multiple$-$server, multiphase system

C$)$ multiple$-$server, single$-$phase system

D$)$ single$-$server, single$-$phase system

E$)$ single$-$server, parallel phase system