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
Covering an area of 972，000 square kilometers, Greenland National Park is one of the largest parks in the world, including both the highest parts of the Northern Hemisphere's largest ice cap and the world's northernmost land area.
For thousands of years, various Inuit (因纽特人的) cultures have lived and survived here thanks to the Arctic species of animals. Today, the hunters from Ittoqqortoormiit are the only ones who have regular access to the area. They go on dogsled (狗拉雪橇) trips and hunt in the National Park. The only people who live in the vast area are a total of about 40 people in five settlements.
·The Sirius Patrol has its main base at Daneborg in Northeast Greenland. The Patrol is responsible for monitoring the area by dogsled. They also have to control exploration and protection rules in the National Park.
·Mestersvig is hiring people, and especially in summer, there is a lively activity in the old mining (采矿) town.
·The weather stations at Station North and in Denmark's Harbour are also staffed. The main task of the staff in Denmark's Harbour is to launch a weather balloon twice a day with measuring instruments.
·Zackenberg Research Station is about 450 kilometers north of Ittoqqortoormiit. Research is conducted here into the effects of climate change. The station is located in a high Arctic climate area that reacts earlier than other areas to changes in global weather.
Each year the National Park is the goal for a growing number of scientific explorers. Many also come to explore the tracks of ancient Inuit settlements.
21．Which of the following best describes the Greenland National Park?
A．Speciespoor. B．Extremely cold. C．Easily accessible. D．Highlydeveloped.
22．Where do people probably go for the protection of the National Park?
A．Daneborg. B．Mestersvig.
C．Station North. D．Denmark's Harbour .
23．What is the main task of Zackenberg Research Station?
A．Studying climate change. B．Predicting local weather.
C．Exploring ancient settlements. D．Controlling scientific explorations.
