If a dinner guest is to be late for dinner, he should ______.

A．A man offers his seat to a woman.
B．A woman opens a door for a gentleman.
C．A man walks between two women on the street.
D．A gentleman smokes while walking on the street.

A．at ease
B．puzzled
C．like a fool
D．sorry about himself

A．Social Life in Western Countries
B．American and British Ways of Life
C．Social Customs and Ways of Behavior
D．Promptness Is Important in Social Activities