The true statement regarding the taxonomic system is:
The current taxonomic system is based on the Linnaean classification system.
The Linnaean classification system, established by Carl Linnaeus, is the foundation upon which modern taxonomy is built, although it has been expanded and modified with advancements in genetic understanding. The other statements are incorrect. Not all current living species have been cataloged, nor have all extinct species been cataloged, and while Charles Darwin contributed greatly to the understanding of evolution, he was not the primary creator of the taxonomic system.