The right answer is flamingoes.Concept:Filtering systemIt is a kind of feeding system for birds.This system is mainly present on their beaks.It helps to separate food material from water by filtering.This filtering system is mainly present in birds that feed on bodies of water.For filtering purposes, the beaks of the birds are mainly flat and wide.These are some examples of birds that have a filtering system in their beaks: flamingoes, swans, ducks, etc.?Explanation:FlamingoesFlamingoes have flat and wide beaks.They feed on water bodies.They mainly feed on algae and small crustaceans.So, the filtering system that is present on their beaks helps to filter this kind of food from the water for feeding purposes.Hence, flamingoes have a filtering system in their beaks. Flamingoes is the correct answer.Additional InformationRobin:Its beaks are mainly thin and straight.They feed on insects.So, they do not need any filtering system for their feeding purposes.MacawThis type of species has short and curved beaks.It helps to break nuts and fruits for their feeding purposes.So, they also don't need a filtering system.SparrowThis species has short cone-shaped beaks.They mainly feed on seeds.Filtering system is absent in this species.Robins, macaws, and sparrows are incorrect answers.