There have been dramatic changes to this planet since the early days of its existence. What is the most noticeable is that since the world became industrialized, the (..1..) of animal species that have (..2...) become extinct or have neared extinction has increased. Bengal tigers, for (..3..), which once roamed the jungles in vast numbers, now (..4..) only about 2,300. By the year 2025, it is estimated that they will become extinct. What is alarming about the case of the Bengal tiger is (..5..) this extinction will have been caused almost entirely by poachers, who, (..6..) to some sources are not always in material gain (..7..) in personal satisfy. This is an example of the callousness that is (..8..) to the problem of extinction. Animals such as the Bengal tiger, as (....) as other endangered animals, are valuable parts of the world's ecosystem. International laws protecting these must be (..10..) to ensure their survival and the survival of our planet.
1. B. number
2. B. all
3. C. instance
4. A. number
5. A. that
6. B. according
7. C. as
8. B. contributing
9. C. many
10. A. enacted
