What Is Life? 2nd Edition by Jay Phelan

Exercise 3

Even though there is a carbon cycle, carbon dioxide levels around the world seem to be rising. Which of the following best explains why this is so?
A) Animals give off carbon dioxide during their normal metabolism.
B) As the atmosphere heats up, it can contain more carbon dioxide.
C) The destruction of coral reefs leads to increased levels of carbon dioxide.
D) More carbon dioxide is being given off by ocean waters as they heat up.
E) The burning of fossil fuels releases more carbon dioxide into the atmosphere.