All the organisms are running across a continuous evolution system and the organisms including the human beings do not fit into the classification system of the time. the classification system changes according to the changes in the organisms species and they have to be incorporated soon in new groups.
I am pretty sure it is animal cells and plant cells considering I learned that last year in 6th grade
Answer: D) Centrioles
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Centrioles are only found in animal cells and they help during cell division. They organize the spindle fibers that help elongate the cell and separate the chromosomes.