“经过差不多70年的努力，葡萄牙人终于从非洲最北端沿非洲西海岸南下到达最南端，其中的艰难险阻是难以想象的……进入印度洋后，下面的路程就比较顺利了，随后葡萄牙人依靠阿拉伯人的帮助很快来到东方。”材料中“来到东方”的葡萄牙人是(　　)

从框里选择填入对话相应空白处的适当选项

A: Hello, this is Ann.Is that Helen ?
B: Yes, speaking.
A:Helen, The happy weekend is coming. ____ 
B: Yes, I’m not busy. I've already finished my homework.
A: ____ 
B: I’ve no idea. What about you ?
A: Let me see. Let's do something interesting and helpful. ____ 
B: Certainly. Where?
A: In the new museum.
B: Oh, I remember. I heard of it last week. ____ 
A: By bike. It's Saturday tomorrow. The traffic must be heavy, I think.
B: I agree. ____ 
A: At the gate of our school at nine in the morning.