Answer: Technically B and C are the answers. Chat was the orginial social media before My Space came along. Then Social Media sites became the donminate player. I think today it falls more in line with Social News Sites. But technically both B and c are correct.
The question is vague, but answer B is absolutely incorrect so by default choice A is correct ... "good" is hard to define and your vision can be corrected by glasses allowing you to drive, etc.
