Based on your options and understanding of this question, we would want to find an answer that would consists of the concern of both the social media, and how people and the society would view this. We can see in the last option on how it would read "information that is shared can often lack credibility and reliability". We can see that in social media and the environment of the social media would be a very lacking in the sense of both credibility and reliability. And therefore, your last question would most likely be your answer.
