Answer :
It should be Mutalistic symbionts since they can't digest the cellulose they obtain from plants.
Answer;
Mutualistic symbionts
The cattle and the microorganisms are mutualistic symbionts.
Explanation;
Symbiosis involves the interactions of two species living together; it may be mutualistic, parasitic or commensal.
Mutualism is a type of symbiotic relationship where both organisms involved benefit from the interaction.
For instance in this case; between cattle and microorganism; Cattle depend on microorganisms in their digestive tract to digest the cellulose in their diets, and in turn microoganisms gets nutrients and habitats from the cattle.