Which transport layer protocol provides best-effort delivery service with no acknowledgment receipt required?

Which transport layer protocol provides best-effort delivery service with no acknowledgment receipt required?
A . HTTP
B . IP
C . TCP
D . Telnet
E . UDP

Answer: E

Explanation:

UDP provides a connectionless datagram service that offers best-effort delivery, which means that UDP does not guarantee delivery or verify sequencing for any datagrams. A source host that needs reliable communication must use either TCP or a program that provides its own sequencing and acknowledgment services.