Which function fundamentally distinguishes TCP from UDP in network communication?

💡 Explanation:

Transmission Control Protocol (TCP) is a connection-oriented protocol that ensures the reliable, sequential, and guaranteed delivery of data packets through mechanisms like sequencing and acknowledgments. User Datagram Protocol (UDP) is a connectionless protocol that offers faster, lower-overhead transmission but provides no guarantees of delivery or packet order. Thus, guaranteed delivery and ordered packets is the key distinguishing function.