Which of the following programs is used for bypassing normal authentication for securing remote access to a computer?

A backdoor is a covert entry point intentionally installed on a system that circumvents normal authentication and security controls, allowing an attacker to regain remote access without triggering standard login or authorization procedures. Backdoors are commonly deployed by attackers after initial compromise to maintain persistent, stealthy access to the target system.

A worm is self-replicating malware that propagates across networks by exploiting vulnerabilities, but it does not specifically function as a remote access tool that bypasses authentication.

Adware is software that automatically displays or downloads advertising content to the user, and has no capability to bypass authentication or provide remote access.

Spyware secretly monitors and collects user activity, keystrokes, or credentials, but it does not serve as a mechanism for bypassing authentication to gain remote system access.