What is the purpose of this excerpt from a speech? Global warming should matter to everyone, not just climate scientists and environmentalists. The primary cause of global warming is human actions. So we should take full responsibility for it. We must understand that if we continue to release excessive greenhouse gases, global warming will only get worse. Sea levels will continue to rise. More glaciers will melt. And local temperatures will increase. Increased temperatures, in turn, will change the pattern of rainfall. Extreme weather events will expand tropical diseases and affect the seasonal pattern and the balance of the ecosystem. In the end, it will drastically change the way we live.

A.
to convince the audience that global warming is a natural phenomenon
B.
to inform the audience how global warming results in water pollution
C.
to entertain the audience by sharing interesting facts about global warming
D.
to raise awareness in the audience about the effects of global warming
E.
to inform the audience how global warming reduces the human lifespan