The extinction of many species of birds has undoubtedly been hastened by modern man; since 1600 it has been estimated that approximately 100 bird species have become extinct over the world. In North America, the first species known to be annihilated was the great auk, a flightless bird that served as an easy source of food and bait for Atlantic fishermen through the beginning of the nineteenth century.
Shortly after the great auk’s extinction, two other North American species, the Carolina parakeet and the passenger pigeon, began dwindling noticeably in numbers. The last Carolina parakeet and the last passenger pigeon in captivity both died in September 1914. In addition to these extinct species, several others such as the bald eagle, the peregrine falcon, and the California condor are today recognized as endangered; steps are being taken to prevent their extinction.
The paragraph following this passage most probably discusses … .
Select one:
a. what the bald eagle symbolizes to Americans
b. how several bird species became endangered
c. other extinct species
d. what is being done to save endangered birds