Which description matches the TCP protocol?

• A. UDP
• B. TCP
• C. ARP
• D. ICMP

Answer: (B)

TCP is a connection-oriented transport protocol that guarantees reliable, in-order delivery of a stream of bytes. It establishes a connection with a three-way handshake, numbers and acknowledges segments, and uses flow control and congestion control to manage data flow and network conditions. This combination—setup of a connection, reliable delivery with sequencing and acknowledgments, plus handling of flow and congestion—defines TCP and distinguishes it from other protocols.

In contrast, UDP is described as connectionless and unreliable, ARP maps IP addresses to MAC addresses on a local network (not a transport protocol), and ICMP is used for control messages and error reporting rather than delivering user data. So the description that fits TCP emphasizes reliability, ordering, and a formal connection setup.