对于航向信标的场地保护区范围，下述说法正确的是（）。

A.由一个长方形区域组成

B.由一个圆形和长方形合成的区域组成

C.由一个圆形的区域组成

D.由一个35度角的扇形区域组成

WebSQL is a SQL-like (71) language for extracting information from the web. Its capabilities for performing navigation of web (72) make it a useful tool for automating several web-related tasks that require the systematic processing of either all the links in a (73) , all the pages that can be reached from a given URL through (74) that match a pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common (75) Interface.

A．hypertext

B．page

C．protocol

D．operation