Even though there is a carbon cycle, carbon dioxide levels around the world seem to be rising. Which

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