###Rationale: Ohngren's classification: Imaginary plane is drawn extending between medial canthus of eye and angle of mandible Supra structures, growth above the plane has poor prognosis Infrastructures, growth below the plane has good prognosis Lederman's classification: It uses two horizontal lines of sebileau: one passing through the floor of orbit and another passing through the floor of antra Divides into supra structures, mesostructures and infrastructure.

###Answer: OPTION A IS CORRECT.
###Question: Ohngren's classification of maxillary sinus carcinoma is based on
###Options:
A. Imaginary plane between medial canthus of eye and angle of mandible
B. Imaginary plane between lateral canthus of eye and angle of mandible
C. Two horizontal lines, one passing through floor of orbit and other through floor of antrum
D. None
