Biology - Organisms and Populations Question with Solution | TestHub

The ecological hierarchy represents the arrangement of biological organisms in relation to one another. It starts from the most basic level and goes up to the most complex level.

The levels of ecological hierarchy in increasing order of complexity are:
Organism $\to$ Population $\to$ Community $\to$ Ecosystem $\to$ Biome $\to$ Biosphere.

An organism (or individual) is the lowest and most basic level of ecological hierarchy. It refers to a single living entity that can function independently.

Answer: Organism