The correct answer is B. Telnet.
Telnet is a network protocol that allows a user to log in to a remote computer and execute commands on that computer. It is a text-based protocol, which means that all communication between the client and server is in the form of text. Telnet is often used to manage servers and other network devices.
TCP is a transport layer protocol that provides reliable, ordered, and error-checked delivery of data between applications running on hosts communicating by an IP network.
SMTP is a protocol for sending email. It is a text-based protocol, which means that all communication between the client and server is in the form of text. SMTP is often used to send email from a mail client to a mail server.
FTP is a protocol for transferring files between a client and server. It is a text-based protocol, which means that all communication between the client and server is in the form of text. FTP is often used to download files from the internet.
In conclusion, Telnet is the only protocol that provides a connection to the remote computer in such a way that a local terminal appears to be at the remote side.