(a) The given flow chart represents taxonomic categories showing hierarchial arrangement in descending order.
A is Phylum or Division,
B is Class,
C is Order and
D is Family.
(b) Labelled part C in the given flow chart represents Order. It is a type of taxonomic category with one or more related families sharing certain similar characters. For example, the Family Solanaceae is placed in the Order Polymoniales along with four other related families such as Convolvulaceae, Boraginaceae, Hydrophyllaceae and Polemoniaceae.
(c) Members of labelled part D (Family) share more similar characteristics because the number of similar characters in categories decreases from lowest rank (family) to highest rank (kingdom).
