Which of the following could be a possible cause of a computer being infected by viruses?

• A. Accessing only secure, encrypted websites
• B. Using a computer with updated antivirus software
• C. Regularly updating the operating system
• D. Downloading files from untrusted websites

Answer: (D)

Verified step by step guidance

1. Understand that computer viruses are malicious software programs that can infect a computer when it interacts with unsafe or compromised digital content.
2. Evaluate each option by considering how it affects the risk of virus infection: accessing secure, encrypted websites generally reduces risk; using updated antivirus software helps detect and remove viruses; regularly updating the operating system patches security vulnerabilities.
3. Recognize that downloading files from untrusted websites is risky because these files may contain hidden viruses or malware that can infect the computer upon download or execution.
4. Conclude that among the given options, downloading files from untrusted websites is the most likely cause of a computer being infected by viruses.
5. Remember that practicing safe browsing habits and only downloading files from trusted sources are key preventive measures against virus infections.