问题
单项选择题
WebSQL is a SQL-like (26) language for extracting information from the web. Its capabilities for performing navigation of web (27) make it a useful tool for automating several web-related tasks that require the systematic processing of either ail the links in a (28) , all the pages that can be reached from a given URL through (29) that match a’ pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common (30) Interface.
（30）是（）
A.Router
B.Device
C.Computer
D.Gateway
答案
参考答案：D
解析：
WebSQL是一种类似于SQL的查询查询语言，用于从Web中提取信息。它能够在 Web超文本中巡航，这使得它成为自动操作一个页面中有关链接的有用工具，或是作为搜索从一个给定的URL可以到达的、所有匹配某种模式的页面的有用工具。WebSQL也提供透明地访问索引服务器的手段，这种服务器可以通过公共网关接口进行查询。