This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oncology, Subject name: Medicine
For the following medical conditions, select the associated acid base disturbances.Chronic pulmonary disease on steroids. 
Select and explain. 
A. metabolic acidosis and respiratory acidosis, B. metabolic acidosis and respiratory alkalosis, C. metabolic alkalosis and respiratory acidosis, D. metabolic alkalosis and respiratory alkalosis
C: metabolic alkalosis and respiratory acidosis
Answer: C: metabolic alkalosis and respiratory acidosis 
Explanation: Chronic pulmonary disease often causes respiratory acidosis, whereas the steroids frequently used in therapy may cause a metabolic alkalosis.