Which of the following best defines symbiosis?

Symbiosis is defined as a close and long-term biological interaction between two different species. This definition encompasses a variety of interactions that can be mutually beneficial, harmful, or neutral. The term 'symbiosis' often brings to mind interactions like mutualism, where both species benefit, as well as commensalism, where one species benefits without affecting the other. Additionally, it can involve parasitic relationships, where one organism benefits at the expense of the other. Overall, the essence of symbiosis lies in the depth and longevity of the interactions, distinguishing them from more transient relationships, such as competition or predation. This broad definition captures the complexity of ecological interdependence observed in nature.