<s>[INST] context: For a commuter rushito catch a train, a minute can mean the difference
between dinner with the family and foods in the microwave. What most passengers don't realize
is that their minute is already there.
    Every commuter train that departs from New York Cityabout 900 a d
leaves a minute later than scheduled. If the timetable says 8:14, the train will actually leave at
8:15.In other words, if you think you have only a minute to get that trainwell, relax. You
have two.
    The courtesy minute , in place for decades and published only in private
timetables for employees, is meant for those who need the extra time to get off the platform and
onto the train.
    "If everyone knows they get an extra minute, they're going to waste time doing
unimportant things," explained Marjorie Anders, a spokeswoman for the Metro-North Railroad.
Told of this article, Ms. Anders laughed. "Don't blow our cover!"she said.
    Entirely hidden from the riding public, the secret minute is an odd departure from the
railroad culture of down-to-the-second accuracy. The railroad industry helped invent the concept*
of standard time, and time zones were established in the United States in the 1880s, 35 years
before they were written into law. And most commuters know their train by the accurate minute
it departs. The trains quickly make up the minute:at all other stops, the public timetable is
carried out. The courtesy minute does not exist at commuter railroads in Chicago, Los Angeles,
Philadelphia, or San Francisco. But in New York, the secret minute dates back decades.
    "That's been done forever, from my knowledge," said Jack Swanberg, 70, an unofficial
historian of Metro-North. "I was the trainmaster starting in 1970 and I'm sure it's been the case
since 1870 for all I know." [/INST] question: The courtesy minute was hidden from the public to  _  . | options: A: prevent the passengers' idleness B: .help invent the concept of standard time C: show the railroad company's patience D: follow the ancient tradition of New York City | answer: A </s>