This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
A 40 years old male develops excessive hyperven-tilation. A G reveals pH- 7.5 pCO2 24 mm Hg PO2 88 mm of Hg. True statement is - 
Select and explain. 
A. Respiratory alkalosis, B. Metabolic alkalosis, C. Respiratory acidosis, D. Metabolic acidosis
A: Respiratory alkalosis
Answer: A: Respiratory alkalosis 
Explanation: First step

Determine whether it is acidosis or alkalosis
Increased pH indicates alkalosis

Second step

Inspect HCO3-/CO2 to determine the cause of alkalosis or acidosis.

pCO2 → 24 mm Hg (decreased)

The alteration in CO2 is in sync. with the alteration in the pH, so the alkalosis can be attributed to a decrease in pCO2.
Thus, it is a case of respiratory alkalosis.