Which of the following is true about the TCP protocol in the TCP/IP suite?

• A. It provides end-to-end reliability and ordered delivery.
• B. It is a connectionless protocol.
• C. It is used primarily for broadcasting.
• D. It does not use ports.

Answer: (A)

The essential idea is that TCP guarantees reliable, ordered end-to-end delivery by establishing a connection and managing data with sequence numbers and acknowledgments. TCP is connection-oriented, so it performs a handshake to set up a reliable channel before any data flows. Each byte is given a sequence number, and the receiver sends acknowledgments as data arrives; if an acknowledgment isn’t received, the sender retransmits. This mechanism ensures that data is delivered intact and in order, even if packets take different paths or arrive out of sequence. TCP also uses a sliding window to control the amount of data in transit, providing flow control and helping to adapt to network conditions through congestion control.

It’s not a connectionless protocol, so it does not fit that description. It isn’t used primarily for broadcasting, since TCP targets reliable, end-to-end streams between two endpoints rather than broadcast delivery. And it does use ports to differentiate different applications on a host, which is part of how TCP multiplexes connections.