Answer:
Commensalism
Explanation:
Commensalism refers to the ecological interaction between the organisms of two species wherein one of the organisms is being benefited while the other remains unaffected.
In the given example, the cattle egrets derive their nutrition by feeding on the insects. To increase the feeding rates, these birds follow the grazing animals such as cattle.
As the grazing cattle move, insects are flushed out of the grasses which in turn serve as food for the egrets. Here, the egrets are benefited while the cattle remain unaffected. Therefore, it represents the example of commensalism.