This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Polyp, Subject name: ENT
Antrochoanal polyp arise from? 
Select and explain. 
A. Ethmoid sinus, B. Maxillary sinus, C. Frontal sinus, D. Sphenoid sinus
B: Maxillary sinus
Answer: B: Maxillary sinus 
Explanation: ANSWER: (B) Maxillary sinusREF: Dhingras ENT 5th ed p-188, 4th edition page 164See table of "DIFFERENCES BETWEEN ANTROCHOANAL AND ETHMOIDAL POLYP" in ENT December 2009