题目内容：

Until the invention of the steam engine, humans traveled the earth on foot. The slow travel meant that explorers frequently returned with stories about distant lands: some of them wild tales, some honest descriptions.

Barbara Klion, who has retired, knows what that’s like. As a walker who has toured Australia, Kenya and China on foot, her trips are the modern edition of an ancient tradition. For years, Klion and her husband, now 75 and 80 years old, traveled independently.

Walkers know that seeing the world on foot gives them a rare experience. Often travelers are attracted by local people and customs. They also get a beautiful and lasting impression of the scenery. Walking tours can be done in one’s backyard, but there are several destinations around the world that expose travelers to the best of nature and culture.

What to look for? A famous guide says that the essentials of a quality walk are great scenery, tolerable1 weather, suitable level of difficulty and something like ecology, history or culture. These may seem like unclear instructions, but the fun of walking tours is that many things are determined by the traveler.

Someone who appreciates hot climates, wildlife and flat areas could choose a walking tour in Zambia’s South Luangwa National Park. Travelers who don’t mind the cold and enjoy adventure could hike Patagonia, an area of southern Argentina east of the Andes.

In general, independent travelers can decide how far to go each day, while guests of a tour agency should expect to walk an average of four to eight miles a day. At the Fordland National Park, for example, there are several easy-to-difficult hikes, giving travelers many choices.

1.Which of the following does NOT make a quality walking?

A．Great scenery.

B．Tolerable weather.

C．A helpful companion.

D．Suitable level of difficulty.

2.According to the passage, compared with guests of a tour agency, independent travelers      .

A．can walk farther  B．have more choices

C．face more difficulties D．spend less

3.What’s the author’s attitude towards walking tours?

A．Indifferent.  B．Negative.

C．Worried.      D．Supportive.

4.The best title for the passage might be “       ”.

A．See the World on Foot

B．Barbara Klion, a Great Traveler

C．What to Look for

D．The Fun of Walking