At a basic level， cloud computing is simply a means of delivering IT resources as （）.Almost all IT resources can be delivered as a cloud service: applications， compute power， storage capacity， networking，programming tools，even communication services and collaboration （）。
Cloud computing began as large-scale Internet service providers such as Google，Amazon，and others built out their infrastructure. An architecture emerged: massively scaled， （） distributed system resources，abstracted as virtual IT services and managed as continuously configured， pooled resources. In this architecture， the data is mostly resident on （）“somewhere on the Intemet”and the application runs on both the "cloud servers”and the user’s browser.
Both clouds and grids are built to scale horizontally very efficiently. Both are built to withstand failures of （） elements or nodes. Both are charged on a per-use basis. But while grids typically process batch jobs， with a defined start and end point， cloud services can be continuous. What’s more， clouds expand the types ofresources available —— file storage， databases， and Web services —— and extend the applicability to Web and enterprise applications.
Both are built to withstand failures of （） elements or nodes.
A．entire
B．individual
C．general
D．separate
参考答案：B
解析：
本题考查对英语资料的阅读理解。本段英文简要介绍云计算的概念。云计算主要是将资源看作云服务，包括应用程序、计算能力、存储容量、网络、编程工具，以及通信和协作工具。云计算最初由一些大的Internet服务提供商构建的基础设施而起步，其架构呈现出大规模、水平分布式系统资源、抽象的IT服务、管理持续配置、资源池等特性，数据大多存储于Internet上的某个地方的服务器上，应用程序运行于云服务器和用户浏览器中。 云和网格都针对有效的水平可扩展性，避免节点的单点失效对系统的影响，都按使用付费。它们的区别是网格通常是处理一批有明确定义起点和终点的作业，而云服务是可以连续不断的。另外，云扩展了资源的类型，包括文件存储、数据库和Web服务等，也将适用性扩展到Web和企业应用。