In Herbivores,cellulose Is Primarily Broken Down by

In herbivores,cellulose is primarily broken down by

A) powerful digestive enzymes produced by the herbivore's stomach glands.
B) powerful digestive enzymes produced by the herbivore's salivary glands.
C) helminths living within the herbivore.
D) bacteria living within the herbivore's gastrointestinal tract.
E) powerful digestive enzymes produced by the herbivore's intestinal glands.