Aresearcher investigates a blood disease carried by birds. she isolates an organism from the blood of an infected bird. she finds that the organism is unicellular and has a nucleus, a cell wall, and the ability to produce spores. what kingdom does the organism belong to? a. archaea b. bacteria c. sarcodina d. protista

Note each of them:

Archaea is a single-celled microorganism with no nucleus

Bacteria is a unicellular microorganism with cell walls but lack organelles

Sarcodina is a phylum with temporary extensions of the cell. They can be parasitic.

Protista is an eukaryotic organisms that is not an animal, plant, or fungus.

The organism found is unicellular (rules out Archaea), with cell walls (characteristics of bacteria), and the ability to produce spores.

I believe that Bacteria (B) is your best answer

hope this helps

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