Answer :
Answer:
a. They emit more carbon than they take in
Explanation:
The carbon sinks are basically the natural storage for carbon. The oceans and the forests are some of the carbon sinks, and are the two of the biggest. They have the ability to take in more carbon than they emit back into the atmosphere, thus they are actually keeping the greenhouse effect under control and not letting it increase significantly. A perfect example for carbon sinks are the deposits of coal that the humans have been using since the industrial revolution intensively. The coal is made out of the trees that existed in the Carboniferous, hundreds of millions of years ago, and that carbon was stored deep inside the ground for all that time until the humans intervened.