Which of the following terms refers to the classification rank directly below 'Order'?

The term that refers to the classification rank directly below 'Order' is 'Family.' In the hierarchical structure of biological classification, the sequence typically moves from broader categories to more specific ones.

The order of taxonomy is as follows: Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species. Therefore, following 'Order,' the next specific rank is 'Family,' which encompasses groups of related genera (plural of genus) that share common characteristics.

Understanding this hierarchical classification is key in subjects like biology and taxonomy, as it helps researchers categorize and communicate about the vast diversity of life. Knowing the correct sequence of these categories is fundamental in the study of organism relationships and classification.