Explain the term “Denial of Service” attack.

A "Denial of Service" (DoS) attack is characterized by its aim to disrupt the normal functioning of a targeted server, service, or network. The primary objective of this type of attack is to make the target system unavailable to its intended users by overwhelming it with a flood of traffic or requests. This excessive load prevents legitimate users from accessing the resources they need, effectively "denying" service.

This type of attack can be executed in various ways, including sending a massive amount of requests to the server, exploiting vulnerabilities in applications, or even using botnets—collections of compromised computers. By focusing on overwhelming the system rather than breaching security to steal data or gain unauthorized access, a DoS attack specifically targets the availability aspect of cybersecurity, which is crucial for maintaining the integrity of services provided over a network.

In contrast, the other options describe different types of attacks or aspects of cybersecurity threats. For instance, stealing sensitive information relates more to data breaches, affecting physical hardware pertains to targeted physical attacks or sabotage, and unauthorized access to accounts concerns methods of gaining access to confidential information rather than overwhelming the system’s capacity to function.