What characteristic describes a virus?

Question:
What characteristic describes a virus?

• a network device that filters access and traffic coming into a network
• the use of stolen credentials to access private data
• an attack that slows or crashes a device or network service
• malicious software or code running on an end device

Exam with this question: CCNA 1 Final Exam Answers
Exam with this question: 15.7.2 Check Your Understanding – Identify the Security Term