What are signatures as they relate to security threats?

Question:
What are signatures as they relate to security threats?

• a unique encryption code used by a known attacker
• one or more code patterns within a specific type of malware
• the beginning or end of a malware segment that has a specific cyclic redundancy check number
• the checksum associated with each specific type of malware that is stored in a virus table

Explanation: Antimalware software analyzes code patterns within malware to create signatures that are stored in virus definition tables. Antimalware signature files are constantly being updated because malware is constantly morphing into new strands.

Exam with this question: IT Essentials (ITE v7) Chapter 13 Exam Answers
Exam with this question: IT Essentials 8.0 Module 13 Exam Answers