(5). (单选题) Which of the following ideas is suggested in the passage?(本题2.0分)
A、 In the United States there are twelve million tennis players and six million golfers.
B、 There are 280,000 motorcyclists in the United States.
C、 Many people realize that motorcycling is becoming one of America’s most popular sports.
D、 Motorcycling becomes more common in the future.

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