SaaS refers to:

A$)$ self$-$contained services that communicate with each other to create a working software application.

B$)$ easy$-$to$-$use software tools for displaying Web pages.

C$)$ supplying online access over networks to storage devices and storage area network technology.

D$)$ hosting and managing access to software applications delivered over the Internet to clients on a subscription basis.

E$)$ managing combinations of applications, networks, systems, storage, and security as well as providing Web site and systems performance monitoring to subscribers over the Internet.