The correct answer to this question is D, None of the above. The Poaceae family, also known as grasses, primarily occupy grasslands. They can be found in several ecosystems are they are essential to both plants and animals. There are many characteristics which make grasslands stand out.
The soil itself is one of those main reasons, which is some being too dry or too wet, reduced infiltration, and high in acid. Trees are essential to the grasslands because they help the grasslands grow and provide them with a location to do so. Another reason why trees are important is that they produce oxygen and carbon dioxide.