Final answer:
The element not essential to geography, considering the content provided in the TEKS objectives, is B) Animal systems, since the objectives revolve around human-related geographical components.
Step-by-step explanation:
When examining the essential elements of geography, it is important to address human systems, places, and regions as they are integral to understanding the spatial and functional aspects of geography. The element that is not considered essential to geography in the context of the provided TEKS objectives, including WG.2A, WG.5A, WG.6A, WG.11A, WG.9A, WG.9B, and WG.14C, would be B) Animal systems. While animal systems can have a role in geographic studies, human geography primarily focuses on the relationship between people and places, as well as the structures created by human societies such as political, economic, social, and cultural elements that shape regions.