Computer Science

Encryption is the process of converting information or data into a code to prevent unauthorized access, ensuring data confidentiality. Decryption is the reverse process, while modulation and decoding are unrelated to data security in this context.

Backup and Disk Defragmenter are standard system tools used for system maintenance and file management. Virus scanning is generally considered a security or utility application rather than a built-in system tool.

A Trojan Horse is a type of malicious code that is loaded onto a computer without the user's knowledge and runs against the user's wishes by disguising itself as legitimate software. Spyware collects information covertly but may not necessarily run against user wishes in the same way. Therefore, Trojan Horse is the most accurate answer.

Ransomware primarily functions by encrypting the victim's files and then demanding a payment (ransom) to restore access. This is its main malicious purpose, distinguishing it from other types of malware.

Malware is a general term for software designed to harm or exploit any programmable device, including computers. While a virus is a type of malware, malware encompasses viruses, worms, trojans, and other harmful software, making it the most accurate answer.

Using a firewall helps to control incoming and outgoing network traffic based on predetermined security rules, thereby reducing the risk of unauthorized access when connected to the internet. Other options do not directly prevent unauthorized access as effectively.

Antivirus software is specifically designed to detect, prevent, and remove viruses and other malicious software from a computer, making it the appropriate choice for virus protection.

A boot sector virus specifically infects the system's boot sector, which is the part of a storage device that contains the code to start the operating system. This allows the virus to execute before the OS loads, making option B correct.

Flaming refers to sending messages with angry, antagonistic, or hostile content, typically in online communication. This matches the description in the question, making option A correct.

In computer communication, "Verification" refers to the process of confirming a user's identity, which is known as authentication. This ensures that the user is who they claim to be before granting access.