A、The place where one can make a fortune. B、Something people like or love. C、The fruit which horses like to eat. D、Good luck to

Many American cities have nicknames.(22)These can help establish an identity, spread pride among citizens and build unity. A few years ago, some marketing and advertising experts were asked to name the best nickname for an American city. The winner was the nation’s largest city, New York. The top nickname was The Big Apple. You might wonder how New York got this nickname.(23)In the early 1970s, the city had many problems. The number of visitors was falling. So a campaign was launched to give the city a new image. The head of the New York Conventions and Visitors Bureau decided to call the city "The Big Apple." There are several explanations for where this name came from.(24)Language expert Barry Popick says John Fitzgerald, a writer for a New York newspaper, used the name "The Big Apple" to mean New York in the 1920s. Mr. Fitzgerald wrote about horse races.(25)In horse racing, the expression meant "the big time," the place where large amounts of money could be won. He heard the name used by men who worked at a racetrack in New Orleans, Louisiana. Mr. Fitzgerald wrote: "The Big Apple. The dream of every lad that ever threw a leg over a thoroughbred and the goal of all horsemen. There’s only one Big Apple. That’s New York. " However, it is not the only nickname for America’s largest city. Barry Popick’s web site lists almost 100 nicknames that describe New York.
22. What can we infer about nicknames from the passage?
23. Why did New York get the nickname "The Big Apple" in the 1970s?
24. According to Barry Popick, who used "The Big Apple" to describe New York in the 1920s?
25. What does "The Big Apple" mean in horse racing?