Answer:
So the conclusion is that in presence of air net force acting downward reduces for feather and hence falls slower than coin. But in absence of air resistance, net downward force is just equal to force due to gravity which is same for both coin and feather and hence they fall down at the same rate.
Its actually C. I did the question on USA test prep and it said the correct answer was C.
Earth is the center according to the geocentric model.
