This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Myasthenia Gravis and Muscular dystrophy, Subject name: Medicine
Which of the following is not seen in Horner syndrome? 
Select and explain. 
A. Mydriasis, B. Ptosis, C. Anhidrosis, D. Enophthalmos
A: Mydriasis
Answer: A: Mydriasis 
Explanation: Horner syndrome Characterized by damage to sympathetic chain FEATURES ARE- S Sympathetic Injury A Anhidrosis M Miosis P Ptosis L Loss of ciliospinal reflex E Enophthalmos Note: Pan coast tumor (Ca. lung) also can contribute to develop Horner syndrome