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The peregrine falcon, a predatory bird indigenous to North America, was once in danger of extinction. In the 1960s, scientists discovered byproducts of the pesticide DDT in the birds’ eggs, which caused them to be too soft to survive. The use of the pesticide had been 5 banned in the United States, but the falcons were eating migratory birds from other places where DDT was still used. In order to increase the survival rate, scientists were raising the birds in laboratories and then releasing them into mountainous areas. This practice achieved only moderate success, however, because many of the birds raised 10 in captivity could not survive in the wild.

There is now, however, a new alternative to releases in the wild. A falcon that has been given the name Scarlett chose to make her home on a ledge of the 33rd floor of a Baltimore, Maryland, office 15 building rather than in the wild, and, to the surprise of the scientists, she has managed to live quite well in the city. Following this example, programs have been initiated that release birds like Scarlett into cities rather than into their natural wild habitat. These urban releases are becoming a common way to strengthen the species. Urban homes 20 have several benefits for the birds that wild spots do not. First, there is an abundance of pigeons and small birds as food sources. The peregrine in the city is also protected from its main predator, the great horned owl. Urban release programs have been very successful in reestablishing the peregrine falcons along the East Coast. Though 25 they are still an endangered species, their numbers increased from about 60 nesting pairs in 1975 to about 700 pairs in 1992. In another decade the species may flourish again, this time without human help.

1. What is the main topic of the passage?

2. In line 1, the phrase “indigenous to” could be best replaced by

3. The word “byproducts” in line 3 could best be replaced by which of the following?

4. In line 5, the word “banned” could be best replaced by

5. Which of the following words is closest in meaning to the word “rate,” as used in line 7?

6. In line 7, the word “raising” most probably means

7. Why were the peregrine falcons in danger?

8. The word “releases” as used in line 12 most probably means

9. The word “ledge” in line 14 is closest in meaning to

10. According to the passage, which of the following is NOT a reason why a falcon might choose to live in a city?

11. According to the passage, which of the following are the falcon’s main predators?

12. As used in line 20, the word “spots” could best be replaced by

13. According to the passage, where have the release programs been the most successful?