Cloud computing is a type of Internet-based computing that provides shared computer processing resources and data to computers and other devices on demand. Advocates claim that cloud computing allows companies to avoid up-front infrastructure costs. Cloud computing now has few service form, but it is not including （）. A: IaaS B: PaaS C: SaaS D: DaaS

（）is the use of computing resources(hardware and software)that are delivered as a service over a network (typically the Internet). A: Virtualization B: Intemet of things C: Cloud computer D: Cloud computing

Cloud computing is worth exploring with more benefits than drawbacks.

______is the use of computing resources(hardware and software)which are available in a remote location and deliverd as a service over a network(typically the Internet)． A: Virtualzation B: Internet of things C: Cloud computer D: Cloud computing

（ ）is the "cloud" section of a cloud computing system. A: The front end B: The back end C: Host Computer D: Sever