cell
Dna
Everything involved in the CNS
A: Kingdom
The simplest level at which life may exist is in a cell.
In classifying life on Earth, the largest level of classification is the Kingdom. Thus, it is the most inclusive, because a step up from kingdom would simply be "life".
No, because organisms are made up of organs, and, in turn, are components of ecosystems. The most inclusive biological level would probably be the entire biosphere.
domain
domain
cell
The species is the least inclusive.
Tissues
The kingdom level is the least specific level of taxonomy. It is broader compared to other levels such as phylum, class, order, family, genus, and species.
They are eight general taxonomic categories of classification. Of these, the species level is the least inclusive category. A species describes the basic unit of biological classification.
In biology organisms are organized (in descending order) into kingdoms, phylum, class, order, family, genus and species. In elementary biology the highest level is the kingdom.
domain
maybe the very top level, the canopy level