Environmental gene tags are
The principle of quantitative reasoning explains that ratio, percentage and series logic determine correct calculation. Hence Habitat-specific functional genes from microbial communities fits best because it meets mathematical and logical criteria, as documented in authoritative sources on aptitude and reasoning.
Ref: Wren and Martin, High School English Grammar and Composition, Revised Edition, Chapter 12, discusses vocabulary and comprehension providing guidance for verbal aptitude and logical inference assessment.
