B. Despite the cold, both animals and plants can be found in polar areas.

　　C. Antarctica has not always been so cold as it is today, nor has the Arctic.

　　D. At one time, the weather in Antarctica was so warm and damp that trees grew there.

　　8. What's the main idea of the passage?

　　A. The Arctic is colder than Antarctica.

　　B. The history of the Arctic and Antarctica.

　　C. The discovery in the Arctic and Antarctica.

　　D. The environmental features in polar regions.

　　C

　　Penguins are the number­one attraction for many visitors to Antarctica. If you go on a ship that is allowed to make shore landings, you may see them. But to get a close look at penguins, you have to be smart.

　　First of all, keep in mind that Antarctica's visitor rules require that you remain at least five meters away from the penguins in order not to disturb them. You could easily become responsible for the death of a little penguin or the destruction of an egg if your too­close presence should disturb a penguin parent.

　　If a penguin is trying to move away from you, you must stop what you're doing and back off even if you're farther than five meters away. However, the rules don't prevent a curious penguin from approaching within five meters of you - as long as the bird makes the move, not you.

　　Little penguins, in particular, are quite curious. I've seen several lucky tourists who were astonished to find that little penguins came right up to them. If a penguin comes extremely close to you, remember: you are not allowed to touch or hold them.

　　Here are more tips for getting close to penguins: Ignore the smell: where penguins live is filled with guano (海鸟粪) and the smell takes some getting used to.

　　Be quiet because loud noises make penguins nervous.

　　Fast or sudden movements signal meat­eating animals to penguins, and they react accordingly, so slow down when you walk around them.

　　Since it may take half an hour or more before the penguins get used to you, you need to be patient.

　　Put away your camera - too often people are so focused on getting the pictures that they forget to look with their own eyes, but most of you most memorable experiences in Antarctica will be marked in your mind, not on a roll of films.

　　9. What will happen if visitors disturb penguins according to Paragraph 2?

　　A. Visitors may step on a little penguin.

B. Penguin parents may break their eggs.