ExplanationURL is the name for a web page address. URL stands for Uniform Resource Locator. Every web page that is displayed on the Internet has a specific address associated with it. This address is known as the URL. It tells us the location of the web page being displayed and other related information. As the postal address is required to reach a letter to a person staying anywhere on earth, a unique location (address) of a web element which may be a website or a web page is required in the World Wide Web to view it in the browser. This unique address of the web elements is referred to as a URL. The URL consists of four basic parts, namely, server type, hostname, the folder name, and the filename. Each one of these has a specific function. The €œserver type€ indicates the type of Internet server (Protocol) being accessed. The server type is always followed by €œ://€ and the hostname. The hostname is the Internet address of a remote computer on which the files reside. The folder name indicates the name of the directory in which the files are located. The filename specifies the name of the specific document to be displayed in the browser. The filename itself consists of two pieces of information, the name of the file to be displayed and the file extension, which specifies the file type (. htm for HTML file, . txt for a text file, . bmp for a bitmap image, etc. ) The structure of a URL can be represented as follows: Server type://Hostname/directory/sub-directory/. . . /filenameExample Of URL: www. testbook. comThus, option 2 is the correct answer. Directory: A web directory or link directory is an online list or catalog of websites. That is, it is a directory on the World Wide Web of (all or part of) the World Wide Web. Historically, directories typically listed entries on people or businesses, and their contact information; such directories are still in use today. A web directory includes entries about websites, including links to those websites, organized into categories and subcategories. Besides a link, each entry may include the title of the website and a description of its contents. In most web directories, the entries are about whole websites, rather than individual pages within them (called "deep links"). Websites are often limited to inclusion in only a few categories. Folder: A digital folder has the same purpose as a physical folder €“ to store documents. Computer folders can also store other types of files, such as applications, archives, scripts, and libraries. Folders can even store other folders, which may contain additional files and folders. Folders are designed for organizing files. For example, you might store your digital photos in a "Pictures" folder, your audio files in a "Music" folder, and your word processing documents in a "Documents" folder. Domain: A domain contains a group of computers that can be accessed and administered with a common set of rules. For example, a company may require all local computers to be networked within the same domain so that each computer can be seen from other computers within the domain or located from a central server. Setting up a domain may also block outside traffic from accessing computers within the network, which adds an extra level of security.