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: Ophthalmology
All the following signs could result from infection within the right cavernous sinus except: 
Select and explain. 
A. Constricted pupil in response to light, B. Engorgement of the retinal veins upon ophthalmoscopic examination, C. Ptosis of the right eyelid, D. Right Ophthalmoplegia.
A: Constricted pupil in response to light
Answer: A: Constricted pupil in response to light 
Explanation: A i.e. Constricted pupil in response to light