Read the passage and decide whether the statements are TRUE (T), FALSE (F) or DOESN’T SAY (NI).

Ecological balance is the stability of each species’ population within an environment. However, this state can be upset by the introduction of new species, the sudden extinction of animals, natural disasters or man-made problems. Throughout history, there have been a variety of environmental issues. Some of the most serious problems are the activities of preparing and fighting wars, which can cause serious environmental damage. During the Vietnam War, for instance, dense forests covering large green areas were carpet bombed, resulting in the habitat of numerous species being destroyed.

The ecological balance has been seriously affected by how the world’s population has increased from the industrial age. We have been clearing plants and trees, changing the way to use the land and expanding paved areas for our development. These activities have an impact on both the water and soil quality and ecology. Due to the increasing water demand of different industries, water has been extracted from deeper wells in further areas. In addition, increased paving would not only reduce the amount of water vapor but also contribute to groundwater pollution. Those issues have gotten worse in recent years and caused many consequences.

Scientists have been carrying out the solutions to ecological imbalance for the past two decades. Hopefully, we can deal with the negative effects of industrial development, and more endangered species will be saved in the next 50 years.

Choose the options that best complete the passage. It is not surprising that almost all first-yea...