Answer:
C) Mitochondria
Explanation:
Mitochondria generate most of the heat in endotherms. While many insects are ectotherms (animals in which their heat source is primarily from the environment), others are endotherms (animals which can produce heat internally by biochemical processes).
Animals help plants by pollinating them, helping them to disperse seeds.
Cells are classified as prokaryotic when they lack a defined nucleus.
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