This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and PNS, Subject name: ENT
Angular vein infection may cause thrombosis of: 
Select and explain. 
A. Cavernous sinus, B. Sphenoidal sinus, C. Petrosal sinus, D. Sigmoid sinus
A: Cavernous sinus
Answer: A: Cavernous sinus 
Explanation: (a) Cavernous sinus(Ref. Scott Brown, 8th ed., Vol 1; 965)Angular vein (from the medial angle of the eye) continues as the facial vein which through the deep facial vein communicates with the cavernous sinus through the pterygoid plexus of veins.