Which method can determine the relationship type when both organisms help each other?

The method that identifies a relationship type where both organisms provide benefits to each other is mutualism. In mutualistic relationships, both species engage in interactions that yield positive effects for one another, enhancing their survival, reproduction, or overall fitness. For example, flowering plants and their pollinators, such as bees, exemplify mutualism; the plants benefit from the pollination for reproduction, while the bees gain nourishment from nectar.

In contrast, commensalism describes a relationship where one organism benefits and the other is neither helped nor harmed. Parasitism, on the other hand, involves one organism benefiting at the detriment of another, typically harming the host in the process. Conservation is not a type of symbiotic relationship but refers to the protection and preservation of ecosystems and biodiversity. Therefore, mutualism is the correct term to describe the specified relationship where both organisms help each other.