What is the term for the process by which microorganisms in the rumen of cattle break down complex plant materials into simpler substances for digestion?

Correct option is C

The process by which microorganisms in the rumen of cattle break down complex plant materials into simpler substances for digestion is called fermentation. These microorganisms help convert plant fibers (cellulose) into volatile fatty acids, gases, and other byproducts that cattle can digest and absorb for nourishment.