Which is a piece of software that allows a malicious user to get "root access," or complete control of a computer.Select one:SpywareRansomwarerootkitkeylogger

Answering the Question

To determine which piece of software allows a malicious user to gain "root access" or complete control of a computer, we can examine the options given:

1. Spyware: This type of software is designed to collect information from a computer without the user's consent. While it can monitor user activity, it does not typically provide root access.

2. Ransomware: This is a type of malware that encrypts the user's files and demands payment to unlock them. It can cause significant disruption and loss but does not primarily focus on granting root access.

3. Rootkit: This is a collection of software tools that enables an unauthorized user to gain control of a computer system without being detected. Rootkits are specifically designed to provide root access, allowing the attacker to administer the system with full control.

4. Keylogger: Keyloggers record keystrokes made by a user, usually to capture sensitive information like passwords. Although they can be used maliciously, they do not provide root access on their own.

Final Answer

The correct answer is rootkit, as it is specifically designed to provide complete control of a computer system to a malicious user.