Which of the following guards access points between intranets and the Internet and prevents traffic that is perceived dangerous to the network?

Public-key cryptography

Security tokens

Shared-key cryptography

Firewalls

Social networking sites d. online forumsthe first recognizable social media site,  six  degrees, was created in 1997. it enabled users to upload a profile and make friends with other users. in 1999, the first blogging sites became popular, creating a social media sensation that's still popular today.

You have to write your reactions like what you agree and disagree with

Plug and play means you don’t have to download anything. just plug it in and play.