The Erythrocyte (Red Blood Cell)count Increases After a While When

Multiple Choice

The erythrocyte (red blood cell) count increases after a while when an individual goes from a low to a high altitude because the ________.

A) basal metabolic rate is higher at high altitudes
B) concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
C) concentration of oxygen and/or total atmospheric pressure is higher at higher altitudes
D) temperature is lower at higher altitudes