Answer:
Mutualistic
Step-by-step explanation:
Mutualistic relationship may be defined as a type of biological interaction in which both the organism are benefited from each other. This shows a positive type of relationship between the organisms.
The bird cattle egret perch on cow's back and eats the prey that hurdles the cow, in returns the cow provide food to the cattle egret. Hence, they shows mutual type of interaction with each other.
Thus, the correct answer is option (C).