A、To gain support from the local community. B、To protect it from irresponsible development. C、To make it a better home for black

Two hours from the tall buildings of Manhattan and Philadelphia live some of the world’s largest black bears. They are in northern Pennsylvania’s Pocono Mountains, a home they share with an abundance of other wild lives.
    The streams, lakes, meadows, mountain ridges and forests that make the Pocono an ideal place for black bears, have also attracted more people to the region. Open spaces are threatened by plans for housing estates and important habitats are endangered by highway construction. To protect the Pocono’s natural beauty from irresponsible development, The Nature Conservancy named the area one of America’s "Last Great Places".
    Operating out of a century-old schoolhouse in the village of Long Pond, Pennsylvania, the conservancy’s bud Cook is working with local people and business leaders to balance economic growth with environmental protection. By forging partnerships with people the Conservancy has been able to protect more than 14,000 acres of environmentally important land in the area.
    Cook attributes the Conservancy’s success in the Pocono to having a local presence and a commitment to working with local residents.
    "The key to protecting these remarkable lands is connecting with the local community," Cook said. "The people who live there respect the land. They value quiet forests, clear streams and abundant wildlife. They are eager to help with conservation effort." Questions 19 to 22 are based on the passage you have just heard.
19. Where are the largest black bears living according to the passage?
20. What is the purpose in naming Pocono as one of America’s "Last Great Places "?
21. How many acres of environmentally important land in the area for the Conservancy’s protection?
22. What is the key to protecting these remarkable lands according to the passage?