Final answer:
In the Linnaean taxonomy, the 'species' is the most specific taxon where organisms are capable of interbreeding to produce fertile offspring.
Step-by-step explanation:
The most specific taxon in the Linnaean system of classification, which includes organisms that can mate with each other and produce offspring, is the species. In this hierarchical classification system, species represent the smallest and most exclusive group. Organisms within a species are similar enough to interbreed and produce fertile offspring. The hierarchy of taxa, from the most inclusive to the most specific, is as follows: domain, kingdom, phylum, class, order, family, genus, and species. The Linnaean system was named after the Swedish botanist Carl Linnaeus who originally proposed this taxonomy in the 18th century.