Discover the best answers at Westonci.ca, where experts share their insights and knowledge with you. Get immediate and reliable answers to your questions from a community of experienced experts on our platform. Connect with a community of professionals ready to provide precise solutions to your questions quickly and accurately.

Boundaries of biogeographic realms are usually

A. based on locations of major high and low pressure zones.
B. based on current country delineation.
C. follow the boundaries of biomes.
D. arbitrary, demarcated by Alfred Wallace in the 19th century.
E. climatic and topographic barriers