Which of the following attacks saturates network resources and disrupts services to a specific computer?

A Teardrop attack exploits a vulnerability in TCP/IP fragmentation reassembly by sending overlapping, malformed IP fragments that cause the target system to crash - it does not primarily saturate bandwidth or network resources.

A polymorphic shellcode attack is a code obfuscation technique used by malware to mutate its signature and evade intrusion detection systems, which is unrelated to resource exhaustion or service disruption.

A Denial-of-Service attack works by overwhelming a target system, server, or network with a flood of illegitimate requests or traffic, exhausting available resources such as bandwidth, CPU, or memory. This resource saturation prevents the target from responding to legitimate requests, effectively disrupting or denying service. It is the canonical definition of a DoS attack and the direct match to the question's description of 'saturating network resources and disrupting services.'

A replay attack involves capturing a valid authentication token or data transmission and retransmitting it to impersonate a legitimate user, targeting authentication integrity rather than resource availability.