Which of the following is NOT affected by crossing time zones

A．Crossing time zones will bring much tiredness to travellers.
B．We can hardly adjust our meal patterns after flying.
C．Sometimes an energetic managing director does not realize that his employees are affected by long-distance flight.
D．Businessmen are proud of being chosen to go on long-distance flights because they can bring wealth for the firm.

A．they do not act according to local time
B．doctors advice them to do so
C．they are too busy with their work
D．it is time for breakfast according to local time