What fits the following definition? "A form of electronic communications, was an application for the masses and finally a reason to buy a computer and join the digital revolution."
There are two possible answers to this question, depending on what choices you have been given and how you would define “communication.”
The first choice would be “email.” This is clearly a form of electronic communication. It is clearly something that “the masses” can engage in. It is also something that was coming to be more widely available in the early to mid-1990s when personal computer ownership was increasing. However, it is not completely clear to me that many people were willing to buy computers mainly for the sake of email.
The second choice would be “the internet.” This would be my choice simply because many more people were likely to buy computers to participate in using the internet than were willing to buy them just to use email. My only qualm about this is that the internet might not always be defined as a form of communication since people 15 or 20 years ago did not typically use the internet to communicate directly with one another. However, if you define communication to include things like news sites and blogs, then the internet counts. This would be my choice as the correct answer here.