WHICH IS THE BEST TITLE FOR THE PASSAGE

40. Which is the best title for the passage?

A. The Search for Alternative Sources of Energy B. The Use of Water Products for Energy.

C. Efficient Ways of Disposing of Waste D. New Discoveries in Geothermal Power

V. Choose the best answer to complete the passage.

Solar energy, air and water are renewable resources because there is an

(41)___ supply. However, (42)___ may change if people are not careful with these resources. The

amount of solar energy that reaches the earth depends on the atmosphere. If the atmosphere is polluted,

the solar energy that reaches the earth (43)____ dangerous. If life is going to continue, the air must

contain the correct amount of nitrogen (N), oxygen (O), carbon dioxide (CO2) and other (44)____. If

humans continue to pollute the air, it will not contain the correct (45)___ of these gases.