<prompt> Which of the following is seen in high altitude climbersa Hyperventilationb Decreased PaCO2c Pulmonary edemad Hypertensione Bradycardiaababcacdbcd  <response>: At high altitude, there can be acute changes and changes due to acclimatization.- Acute mountain sicknessDyspnoea, dizziness, tiredness, tachycardia, palpitation, nausea, vomiting etc.At higher altitudes- pulmonary oedema and cerebral oedema may occur.- Acclimatization changesHyperventilation leading to respiratory alkalosisIncreased 2,3DPG- Hb-O2 dissociation curve shifts to right.Increased erythropoietin leading to absolute polycythemia with increased red cell mass.Increased renal excretion of bicarbonateIncreased tissue vascularityIncreased oxidative metabolismIncreased diffusion capacity of the lungIncreased myoglobin 