Answer:
C
Step-by-step explanation:
Having anything you post be permanent, because if it's something embarassing or bad, it'll be stuck there.
The rest are very positive parts of social media for sure, since it's easier to connect with people who are just like you or enjoy the same things as you, and in A, it expands your ability to learn, I mean look at you, learning from my question, that's quite cool aye? XD