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: Radiology
A 50 year old male patient complains of reduced mouth opening. Patient gives h/o RTA 1 week back. Submentovertex view x-ray was taken which revealed zygomatic arch fracture. Which of the following is true regarding the central beam in this x-ray- 
Select and explain. 
A. It is parallel to the image receptor, B. It is directed from skull to the mandible, C. It is centered about 2 cm anterior to a line connecting the right and left condyles, D. It is posterior to a line connecting the right and left coronoid process
C: It is centered about 2 cm anterior to a line connecting the right and left condyles
Answer: C: It is centered about 2 cm anterior to a line connecting the right and left condyles 
Explanation: Submentovertex view-
The central beam is perpendicular to the image receptor, directed from below the mandible toward the vertex of the skull (hence the name submentovertex), and centered about 2 cm anterior to a line 
connecting the right and left condyles.
White and Pharoah, Oral radiology, ed 7th, pg-161