A、Not getting what he wants. B、A custom that is new to him. C、Calling up customers. D、Some of his good friends. B根据选项，推测提问涉及对话的内

W: Whereas European nations have traditionally employed metric units such as meters and grams, the U.S. has employed English units such as feet and pounds.
M: Both systems are now in use in the U.S., though.
Q: What are the two people talking about?

M: I wish I could get used to this American custom of using first names.
W: I usually call just my good friends by their first names.
Q: What is the man complaining about?