Which of the following statements is true about British pub etiquette?

A.It is OK to start up a conversation with someone sitting at a table.

B.You should wait quietly for the waiters coming to serve you.

C.You should tip bar staff in pubs.

D.If you go to a pub with your friends, you should know how to buy the rounds.

正确答案：If you go to a pub with your friends, you should know how to buy the rounds.