Answer :
The three common types of servers are a web server, a network server, and a file server. Personal servers are not typically recognized as a common class of servers in larger networks. Therefore the correct option is a.
The three common types of servers are:
- Web server
- Network server
- File server
A web server stores and delivers the content for web pages to clients that request this information via their web browsers. A network server manages network resources and can serve multiple roles, such as managing users or network traffic. A file server is dedicated to storing and managing files so that other computers on the same network can access them.
Personal servers are generally not considered a common type of server in larger contexts, as they are typically used for individual personal use and do not have the capacity or services associated with serving multiple users or tasks in a network.