Which of the following is not one of the four methods for classifying the various instances of malware by using the primary trait that the malware possesses?

a. Circulationb. Infectionc. Concealmentd. Source

Answer: Source

Explanation: The malware is the software persisting malicious approach to cause the damage/loss. The primary trait of the malware are infection, concealment, etc.

The concealment refer to the malware such as the Trojan horse, and other viruses that has only purpose to cause the malfunctioning in the system. The virus that get into the other software and then damage the system in known as the infectious malware.

The circulation is the transferring of the virus in the circular manner between the system for the damaging. Thus, the only trait that is not the part of the malware is source.