Final answer:
The fundamental niche represents the potential range of conditions suitable for species survival and reproduction, while the realized niche is where the species lives, limited by interactions with other species and environmental factors.
Step-by-step explanation:
The statement that best describes the difference between a realized and a fundamental niche is that the fundamental niche is the full range of environmental conditions (biotic and abiotic) under which an organism can survive and reproduce (the n-dimensional hypervolume where the organism can maintain a viable population).
Whereas the realized niche is the actual set of conditions under which the organism lives, which is influenced and often limited by biotic interactions and competitive exclusion.
Species Distribution Models (SDMs) typically predict the realized niche, as these models are based on empirical distribution data that tends to reflect the constraints placed on the species by its current environment and interactions with other species.
The competitive exclusion principle plays a role here as it postulates that no two species can permanently occupy the same niche; when there is niche overlap and competition for limited resources, evolutionary pressures or competitive advantages will likely lead one species to become predominant while the other could be driven to local extinction.