A、Go through a health check, B、Take little luggage with them. C、Arrive early for boarding. D、Undergo security checks. B从题目选项可以得知

In the next few decades people are going to travel very differently from the way they do today. Everyone is going to drive electrically powered cars(26). So in a few years people won’t worry about running out of gas.
    Some of the large automobile companies are really moving ahead with this new technology. F& C Motors, a major auto company, for example, is holding a press conference next week. At the press conference the company will present its new, electronically operated models.
    Transportation in the future won’t be limited to the ground. Many people predict that traffic will quickly move to the sky. In the coming years, instead of radio reports about road conditions and highway traffic, news reports will talk about traffic jams in the sky(27).
    But the sky isn’t the limit. In the future, you’ll probably even be able to take a trip to the moon. Instead of listening to regular airplane announcements, you’ll hear someone say, "The spacecraft to the moon leaves in ten minutes. Please check your equipment. And remember, no more than ten ounces of carry-on baggage are allowed(28)."