What is the Biological Species Concept?

The Biological Species Concept is defined as a group of organisms that can interbreed and produce fertility viable offspring. This definition emphasizes the role of reproductive isolation, meaning that members of one species cannot successfully breed with members of another species. This concept helps clarify why certain organisms are classified as separate species based on their ability to reproduce successfully within their group, ensuring the continuation of their genetic lineage.

In contrast, the other options present different aspects of species and classification that do not align with the Biological Species Concept. For example, the idea of species coexisting in the same habitat does not account for reproductive capabilities, and organisms exhibiting similar physical traits can sometimes belong to different species that do not interbreed. Lastly, categorizing all organisms under a single classification overlooks the essential idea of reproductive isolation that distinguishes one species from another. Thus, option B accurately reflects the fundamental principle of this concept.