Which type of relationship can be categorized as mutualism?

Mutualism is defined as a type of symbiotic relationship where both species involved benefit from the interaction. This relationship can take many forms, such as pollinators and flowering plants, where the pollinator receives food in the form of nectar while helping the plant reproduce by transferring pollen.

In mutualism, the benefits are typically interdependent, meaning that the survival or reproductive success of both species is enhanced through their association. This relationship is essential to many ecosystems, promoting biodiversity and stability by ensuring that different species can thrive together.

The other types of relationships described in the question highlight different interactions that do not meet the criteria for mutualism. For instance, a relationship where one species benefits at the expense of another indicates parasitism or predation, while scenarios where neither species significantly affects the other represent commensalism. In interactions that involve one species harming another without any advantage to itself, we see features of competition or predation, further distancing these from the mutualistic definition.