The number of common characters among organisms

Step-by-step solution

Maximum similarity occurs in species and this decreases with the increasing rank in the hierarchy. Plantae is the kingdom and is the highest category in the taxonomy that includes all the organisms which share a set of distinguishing characters. Poaceae is the category family and is of higher rank than that of the genus. It consists of one to many related genera, which are more similar to one another than to genera of other families.