This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Medicine
A hypeensive patient who is a chroic smoker presented with recurrent hemoptysis. On examination he had cushingoid features. Investigations revealed raised ACTH levels not suppressed by dexamethasone. The single diagnosis which can account for all his symptoms is 
Select and explain. 
A. Multiple endocrine neoplasia I, B. Pituitary adenoma, C. Adrenocoical adenoma, D. Ectopic ACTH producing tumor
D: Ectopic ACTH producing tumor
Answer: D: Ectopic ACTH producing tumor 
Explanation: Harmonies produced by small cell carcinoma ACTH,ADH,CALCITONIN,GONADOTROPIN. Ref Davidson edition23rd pg 601