阅读下列短文，从每题所给的A、B、C、D四个选项中选出最佳选项。
A
STA Travel, the world's largest students and youth travel agency, beats any price! Every day we're working with our partners around the world to get you (students, teachers and anyone under 26) the cheapest and most comfortable flights and accommodations. This part of www.statravel.com provides great tips for green travel—how to pack, how to leave your house or apartment, and how to plan for your trips. You'll also find a great number of green travel adventure trips to all comers of the world.
Green travel means responsible travel! Leave as little influence as possible on the places you visit and protect the environment both at home and during your trip. Think “Green” when you pack and when you travel. You'll help prevent longterm effects on the communities you leave and visit!
Here's some advice on how to do that.
Before you leave
◆Turn your water heater to its lowest setting.
◆Turn off your water from the outside.
◆Pack suitable clothes in your luggage, none of which is to harm the environment.
While you travel
◆Try products made from recycled materials.
◆Don't buy souvenirs produced from endangered species (物种).
◆Carry a reusable bottle for water and refill it as you go.
◆Use the bathroom in the airport, NOT on the plane. The fuel used for a single flush (冲洗) could run a car for six miles.
21．What do green travelers care most about?
A. Flights. B. Prices. C. Pleasure. D. Nature.
22．What are the readers advised to do during their trip?
A. Use environmentfriendly products. B. Take as much water as possible.
C. Pack as few things as possible. D. Learn about adventure travel.
23．Where can we most probably read the text?
A. In a travel magazine. B. On a travel website.
C. On an environmental poster. D. In an environmental research paper.
