You are concerned with surveying the protozoa in the arboretum soil. While most commonly thought to live exclusively in aquatic environments, protozoa can play an important role in the nutrient cycling that takes place in soil. In addition, protozoa can help maintain the proper balance of bacterial populations within soil, as bacteria are a primary source of food for protozoa. Protozoa are extremely diverse. However, there are three characteristics common to all organisms called protozoa. What are these three characteristics

eukaryotic, unicellular, without a cell wall

Explanation:

Protozoans are single-celled eukaryotes that generally move through cilia, flagella, or amoeboid motion. After their discovery, protozoans were considered as single-cell animals due to their animal behavior (including predation and motility), and because they don't have a cell wall, as observed in algae and plants. Some examples of protozoans include Paramecium, Amoeba, and Trypanosoma. Nowadays, the term 'protozoans' is still used to describe unicellular eukaryotic organisms from the Protista kingdom that are heterotrophs, i.e., unicellular microorganisms that acquire energy and nutrients from other organic sources, especially plant and animal matter.

im not intirely sure but i think the anwser is d relative humidity