Final answer:
A computer virus is named for its ability to replicate and spread to other systems, and for causing harm or disruption to normal computer functions, reflecting similar characteristics to a biological virus. The misconception that viruses originate only from email attachments is incorrect, as they can spread in various ways.
Step-by-step explanation:
The term computer virus is so named for several reasons. Firstly, just like a biological virus, a computer virus replicates itself and spreads to other systems. This is similar to the biological process where viruses infect host cells and use the cellular machinery to produce more virus particles. Secondly, a computer virus can cause harm or disrupt normal computer functions, analogous to how biological viruses can cause disease in organisms. Lastly, while calling it 'contagious' like a biological virus could be a metaphor for how computer viruses can spread from one system to another, it's important to clarify that computer viruses aren't alive and the spread is facilitated through networks or infected media.
However, the statement that a virus always originates from email attachments (d) is incorrect. Computer viruses can be transmitted via various methods, not just email attachments. USB drives, internet downloads, and even exploiting security vulnerabilities can all be sources of computer viruses.
Regarding the process of replication, a computer virus, much like its biological counterpart, must insert its code into a host system or file. This allows the virus to be executed when the host system runs, resulting in the replication of the virus. Viruses typically also have some means of evasion or attack on the host's defenses, which in the case of computers can be akin to escaping detection from antivirus software or exploiting unpatched vulnerabilities.