Assertion : Complexity of classification increases from kingdom to species. Reason : Common characters increase from kingdom to species.

Step-by-step solution

Classification involves hierarchy of steps, in which each step represents a rank or category, called taxonomic category or taxon. All taxa together constitute a taxonomic hierarchy as follows: Species Genus Family Order Class Phylum or division Kingdom. Most common characters among individual members are found in taxon species. Common characters decrease from species to kingdom and members of a kingdom have least number of common characters. Similarly, complexity of classification decreases from species to kingdom