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: Physiology
O2 dissociation curve is shifted to right in all except? 
Select and explain. 
A. Hypercapnea, B. Rise in temperature, C. Raised 2, 3 DPG level, D. Metabolic alkalosis
D: Metabolic alkalosis
Answer: D: Metabolic alkalosis 
Explanation: Ans. is `d' i.e., Metabolic alkalosisHypercapnea (raised CO2), rise in temprature and increased 2, 3 DPG cause righward shift of O2 dissociation curve.Metabolic alkalosis causes leftward shift.