Human Beings,as the Species Homo Sapiens,have Existed on Earth for Approximately

Human beings,as the species Homo sapiens,have existed on earth for approximately

A) 0.00012 (0.12 thousandths) of the earth's history.
B) 1 percent of the earth's history.
C) 10 percent of the earth's history.
D) Homo sapiens originated on Mars, which was much warmer when the sun was younger and its luminosity was greater. Our ancestors colonized Earth as Mars became too cold for habitation, just as we will colonize Venus when Earth becomes colder as the sun's energy fades.