According to the passage, what will be crucial whether in the job or switching to learn the skills you need

A．People greet each other by shaking hands in America.
B．Every country has their own gestures.
C．Learning a culture's body language is very important and. necessary.
D．It is all right to point at things but not at people with the hand and index finger.

A．means that you are number one
B．wants to please you
C．needs to call a waiter
D．expresses his satisfaction with you