A great difference between American social customs and those of other countries is the way
Very often, introductions are made using both first and last names: "Mary Smith, this is John Jones." In this situation you are free to decide whether to call the lady "Mary" or "Miss Smith". Sometimes both of you will begin a conversation using last names, and after a while one or both of you may begin using first names instead. You have a choice: if you don't want to use first names so quickly, no one will think it impolite if you continue according to your own custom.
In the first paragraph the author tells us that ______.
A.Americans do not talk about rank, especially socially
B.Americans feel uncomfortable when talking about rank
C.Americans take interests in social customs
D.Americans don't care much about social rank