Hello Littlefoot2645. I do believe the answer would be that of the process of "mutation," thus it occurs by human interference, specifically, although, initially, naturally-speaking, only occurring by natural selection in onslaught of period time frames.
The parachute was invented 4,000 yrs ago! :)
<span> Amoebic dysentery is caused by the amoeba Entamoeba histolytica. This protozoan exists in nature in the cyst form and is transmitted by contaminated food and water. In patients, the amoebas revert to trophozoites and invade the intestinal lining.
Your answer is C.
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