Answer:
B
Explanation:
Answer B is correct:
Because the biologists are continuing to learn more and more about
such minute organisms, protozoan systematics – that is, the taxonomy (classification) and the evolutionary interrelationships of major groups of protozoa – remains a topic of debate and change, still today.
Some of the rather LARGE and unwieldy taxonomic groupings of past years are particularly subject to revision with expansion of and refinement in the knowledge about the members of those – and related – assemblages. Paradoxically, the protozoa themselves are becoming more difficult to define with precision as our information about them and other microbial assemblages increases. Thus, presenting a single satisfactory circumscribed definition for them is not an easy task.
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Answer A sounds so funny.
Answer C and D are false because Protozoans are usually single-celled and heterotrophic.
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Hope this answer can help you. Have a nice day!
