An Experienced Hiker, H

An experienced hiker, H.A., spends her vacation in Tibet.She complains of often feeling dizzy at high altitudes.Which of the following changes in the cytosol of H.A.'s red blood cells will result in the delivery of more oxygen to her tissues at the relatively low pO₂ on Mount Everest?

A) A decrease in methemoglobin reductase activity.
B) A higher rate of γ-globin gene transcription in red blood cells.
C) An increased blood pH.
D) An increase in the 2,3-BPG concentration.
E) An increase in the carbon dioxide partial pressure.