根据对话内容，从下面方框中选出恰当的句子补全对话。

A: Ben, I have some questions about your country, Canada.

B: OK. What do you want to know?

A:

B: We're supposed to shake hands.

A: For example, when a party is at seven o'clock, do you get at seven?

B:

A: Are you supposed to take a gift when you visit someone?

B:

A: What about seeing friends?

B: We have to call them first and make plans to see friends.

A: Thanks. Now, I'm ready.

A. How about time? B. Can you drop by friends' homes without calling? C: Yes, it's polite to take some flowers. D. No, we can go about fifteen minutes late. E. What are you supposed to do when you meet someone for the first time?