This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cushing Syndrome, Subject name: Medicine
Which is the most common clinical feature of Cushing syndrome? 
Select and explain. 
A. Moon facies, B. Purplish skin striae, C. Hypokalemic alkalosis, D. Weight gain
D: Weight gain
Answer: D: Weight gain 
Explanation: The most common presentation of Cushing syndrome is Obesity or Weight gain. Clinical features Frequency Weight gain 80% Moon facies 75% Purplish skin striae 65% Hypokalemic alkalosis 15%