The security threat which Dan's laptop is still vulnerable to is: d. Malcious USB.
A laptop can be defined as a small, portable computer that is embedded with both a mousepad and keyboard, and it is usually light enough to be placed on an end user's lap while he or she is working.
In this scenario, Dan's laptop is still vulnerable to malicious universal serial bus (USB) even though he has decided not to connect his laptop to any network and made sure his laptop was updated with the latest virus definitions and security patches.
Read more on a laptop here: https://brainly.com/question/26021194
