The highlight word “it” in the passage refers to__...

B

- Hướng dẫn giải

I think I am a Facebook addict. I log on to Facebook everyday to chat to my friends real friends and loads of online friends. Sometimes I have ten conversations going at the same time. I upload photos and update my Facebook profile all the time. But recently I’ve started to feel worried if I am offline for more than a few hours. And then last week I forgot to meet a real friend because I was online! I’ve realised I could have a problem. So I’ve decided to give it up for a while.

It thay thế cho từ Facebook.