Final answer:
Systematics is the scientific field that categorizes organisms based on their evolutionary relationships and directly contributes to our understanding of phylogeny, which is the evolutionary history of organisms.
Step-by-step explanation:
The relationship between systematics and phylogeny is integral to the study of biology. Systematics involves organizing and classifying organisms based on evolutionary relationships, which is the central focus of phylogeny. Essentially, systematics uses a myriad of data from fossils, organism morphology, molecules, and DNA to construct the phylogenetic tree of an organism.
Option c) of the given choices is correct: Systematics is the classification of organisms based on evolutionary relationships, which is the focus of phylogeny. The various levels of taxonomic classification systems provide a hierarchical structure to organize living organisms, further illustrating the close relationship between systematics and phylogeny.
In terms of their relationship, systematics equips scientists with the tools to identify and categorize the vast diversity of life, with phylogeny offering a framework to understand how these diverse forms are interconnected through common ancestry and evolutionary history.