Part 2: Read the text below and choose the best answers

Fires play an important role in the natural changes that occur in Earth’s ecosystems. The diversity of plant and animal life in the world’s forests, prairies, and wetlands is (partly) dependent on the effects of fire. It results when matter burns beyond its combustion point and it releases energy in form of heat energy. Fire has been important for the survival of man in the following ways. Firstly, fire is used for cooking food. Most of the food we eat is usually cooked. Eating raw food has been in the decrease due to health concerns. Secondly, fire is used for boiling water. Water is another important part of our life. Most of the water sources like rivers are not protected and this creates chances of water contamination. Boiling, instead of use of chemicals in water treatment will save you the side effects which come along with excessive use of chemicals. For many other reasons, fire is important to human’s life.

Fires effect______