According to your text, at what point did the concept of social media start to become more serious and professional?
A. after Y2K and the bursting of the dot-com bubble
B. when the Internet first came on the scene
C. after the emergence of smartphones
D. when sites like Facebook became popular
E. with the advent of blogs and 24-hour news sites
Answer: A. after Y2K and the bursting of the dot-com bubble