The smallest and most exclusive grouping category is species.
Answer:
<h2><u>
A. Having a nucleus</u></h2>
Explanation:
Many organisms have nuclei, but certain types of one-celled prokaryotes and bacteria do not have one.
Inheritance of Traits by Offspring Follows Predictable Rules. Genes come in different varieties, called alleles. Somatic cells contain two alleles for every gene, with one allele provided by each parent of an organism.
The concentration of CO2 would drastically increase.