Which type of software is designed to gain elevated privileges to control a computer?

The correct choice is software designed specifically to gain elevated privileges on a computer system, allowing it to control various parts of that system without the user's consent or knowledge. This type of software, known as a rootkit, operates by embedding itself deep within the system and often disguises its presence, making detection and removal difficult.

Rootkits function to hide processes, files, and system data to maintain control over a compromised system. By obtaining elevated privileges, rootkits can manage critical system functions, enabling malicious actors to execute commands, perform surveillance, and further infiltrate the system without drawing attention.

In contrast, botnets refer to a network of infected devices controlled by a single entity to perform tasks like launching distributed denial-of-service (DDoS) attacks. Keyloggers monitor and record keystrokes to capture sensitive information such as passwords. Ransomware encrypts files on a victim's machine and demands payment for decryption. Each of these types of software serves different purposes but does not focus on elevating privileges in the way a rootkit does.