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: Surgery
During extraction of the upper first molar, the mesio buccal root is missing and is suspected to have been pushed into the maxillary sinus.
The best position for the patient immediately after the incident is 
Select and explain. 
A. To position the patient upright, B. To position the patients in a semi inclined posture to visualize the perforation, C. Trendelenberg position, D. Reverse trendelenberg position
A: To position the patient upright
Answer: A: To position the patient upright 
Explanation: None